Why do DSLR's still use mirrors?
Roger N. Clark (change username to rnclark)
posts to see things haven't changed much here. I didn't see
a real answer so here is one major difference between DSLRs
and P&S cameras that does not seem to have been discussed.
----
Why do DSLR's still use mirrors? One answer is simple and due
to the requirements of predictive autofocus and tracking of
moving subjects. Predictive autofocus systems provide the fastest
autofocus and fastest autofocus tracking technology currently
available in consumer and professional cameras, both film and digital.
In general, the cameras that fit in your pocket are small low-end
cameras that have slow response times. But even if you find one with
low shutter lag, it will not be of much help on subjects moving
toward or away from your camera. For such a moving subject,
the full press shutter lag is only a small part of the story
in getting a sharp picture.
Many cameras have what is called "Live View." Live view is an electronic
method of reading the "digital" sensor and displaying the result on
an LCD screen. The term "Live View" is a misnomer. It takes time
to read out the sensor, and the more pixels the sensor has, the more
time it takes. Very high speed electronics in high end cameras can
read out at rates of around 100 million pixels per second. On a
10-megapixel camera, that means the time to read out is about 1/10th
second (100 milliseconds). On lower cost cameras, slower
electronics are used, so the readout times can be longer. It also
takes time to send that data to the LCD. On some cameras, the shutter
speed can also influence the cycle time, adding another delay. All
this means that "Live View" is actually delayed view. Often this
delay is longer than 100 milliseconds, and that means when you
press the shutter the subject is in a slightly different position
than what you see on the LCD screen. This is another factor in fast
action photography and why those who do such photography usually choose
an optical viewfinder. But it is not the main factor. The main factor
is predictive autofocus.
P&S cameras, especially small cheaper ones use the sensor for autofocus
using a contrast detection method. The lens is moved, the sensor read out,
and the contrast checked, the lens moved, the sensor read out, the
contrast checked and if it is getting better keep moving in that direction,
if not, go back, hunting for best focus.
The full press shutter lag, the time from when you press the
shutter to when the camera actually takes the picture, is the best
time for a static (not moving) subject in good light. If the subject
moves, the camera gets confused because the search for the best focus
is continually moving too. That increases the lag time. You can experience
such increased lag on static subjects too if you are swaying back and forth:
the camera to subject distance is changing, confusing the camera. I
have often had P&S cameras take 2, 3 and more seconds to take the picture
when their shutter lag is rated about 1/2 second due to these effects.
For static subjects, a DSLR does what is called a phase detection: the
phase is measured which tells the camera how much the subject is out of focus.
The camera calculates how much to move the focus and does that in one step.
No second check is required. For moving subjects, put the camera in
what is called predictive autofocus and the camera monitors the phase
of the focus as the lens is moved (or not moved). The changing phase tells
the camera what direction the subject is moving and how fast, it then moves
the focus to the best position but also continually tracks it. Even more
impressive is that the camera knows its own shutter lag and predicts where
the best focus will be when the shutter actually opens and sets the lens
to that point.
When holding down the shutter on a DSLR and taking multiple frames,
each time the mirror drops, is allows you to see the subject to help
you track the subject, but the phase detection system does another
measurement of the focus. With each measurement it continually tracks
the focus, the velocity and the changing velocity. The phase detection
system in DSLRs is a set of optics and sensors behind and below the
reflex mirror. Because of the requirements of a phase detection
system design, a mirror is necessary, thus reflex mirrors are not likely
to go away. One could do this with beam splitters, but that loses
light, compromising light for the phase detection system, light metering
system and the picture you want to obtain. Again, the reflex mirror
serves a very important part of the phase detection system so is
not likely to go away.
Here is a demonstration of autofocus tracking of a DSLR:
http://www.clarkvision.com/photoinfo/tracking.action.with.autofocus
Test your shutter lag in your camera at:
http://www.shooting-digital.com/columns/schwartz/shutter_release_test/default.asp
Think of this example: your baby is about to take its first step.
You grab the camera aim, and in a blink of an eye the event
is over. So did you get the picture (or several)?
P&S: Unlikely. The baby does two steps and falls; the camera finally
focuses and gets a picture of the baby on the floor. That's
assuming the camera had "instant on," otherwise the you may
have simply watched the event as the camera slowly turned on.
DSLR in single shot mode all focus point enabled: No! The camera
focused on the wall in the background. ;-)
DSLR in single shot mode, one focus point on the baby:
One frame in focus then as the baby moves forward, successive frames
are increasingly out of focus.
DSLR in predictive autofocus mode, one focus point on the baby:
All frames in focus. Many excellent pictures of the event.
The difference in "focus lock" versus predictive autofocus:
In predictive autofocus the camera fires when you press the shutter
all the way, regardless of where the focus is. If the camera
locked onto the subject and is tracking it (and its speed can
be tracked by the lens AF speed) the prediction is usually
quite good and stays in excellent focus, or, with some slower AF
consumer lenses and bodies, at least better focus than if using
single shot mode on moving subjects.
Bottom line: if you want to take photographs of things in action that
may be moving toward or away from the camera, choose a camera with
predictive autofocus. All DSLRs that I know of have predictive
autofocus. I do not know any P&S cameras with predictive autofocus.
One may use "pre-focus" on cameras without predictive autofocus.
With this method, the photographer must anticipate where the peak
action will occur, set the focus for that positions and wait.
This can work well for things like the finish line of a race.
Unfortunately if the best action occurred at a slightly
different position, you miss the best image. That is where
predictive autofocus shines.
Roger
http://www.clarkvision.com/photoinfo/dslr.mirrors.and.autofocus
Eric Stevens
to rnclark)" <user...@qwest.net> wrote:
--- snip ----
>Test your shutter lag in your camera at:
>http://www.shooting-digital.com/columns/schwartz/shutter_release_test/default.asp
That seems a better test of my reaction time than anything else.
--- snip ----
Eric Stevens
Hank Thomas
LOL!!! The N.Clark spamming moron is BACK spewing his ignorance and stupidity
again!!
LOL
On Thu, 06 Nov 2008 21:16:18 -0700, "Roger N. Clark (change username to
rnclark)" <user...@qwest.net> wrote:
>I was asked to comment on P&S versus DSLRs. I only read a few
>posts to see things haven't changed much here. I didn't see
>a real answer so here is one major difference between DSLRs
>and P&S cameras that does not seem to have been discussed.
>----
>
>Why do DSLR's still use mirrors? One answer is simple and due
>to the requirements of predictive autofocus and tracking of
>moving subjects. Predictive autofocus systems provide the fastest
>autofocus and fastest autofocus tracking technology currently
>available in consumer and professional cameras, both film and digital.
>
>In general, the cameras that fit in your pocket are small low-end
>cameras that have slow response times. But even if you find one with
>low shutter lag, it will not be of much help on subjects moving
>toward or away from your camera. For such a moving subject,
>the full press shutter lag is only a small part of the story
>in getting a sharp picture.
You're a bit late, moron. There have been quite a few threads where people
tested their P&S cameras and showed them to be much faster than your beloved and
wrongly worshipped LOW-END LOSER'S DSLR.
LOL
>
>Many cameras have what is called "Live View." Live view is an electronic
>method of reading the "digital" sensor and displaying the result on
>an LCD screen. The term "Live View" is a misnomer. It takes time
>to read out the sensor, and the more pixels the sensor has, the more
>time it takes. Very high speed electronics in high end cameras can
>read out at rates of around 100 million pixels per second. On a
>10-megapixel camera, that means the time to read out is about 1/10th
>second (100 milliseconds). On lower cost cameras, slower
>electronics are used, so the readout times can be longer. It also
>takes time to send that data to the LCD. On some cameras, the shutter
>speed can also influence the cycle time, adding another delay. All
>this means that "Live View" is actually delayed view. Often this
>delay is longer than 100 milliseconds, and that means when you
>press the shutter the subject is in a slightly different position
>than what you see on the LCD screen. This is another factor in fast
>action photography and why those who do such photography usually choose
>an optical viewfinder. But it is not the main factor. The main factor
>is predictive autofocus.
LOL!! He doesn't even know how to use live-view nor how it works. The only "lag"
is the EVF/LCD refresh rate, which is 60 to 120 fps or faster. The live-view is
accurately relaying the chosen shutter speed. But you're too amazingly stupid to
realize why that is of great benefit.
Rather than address all your ignorance and stupidity one by one with the respect
that a better person would deserve, it's much easier to just list here all the
FACTS that disprove everything you have ever said and believed in your sorry
excuse for a life. You're only worth canned replies.
1. P&S cameras can have more seamless zoom range than any DSLR glass in
existence. (E.g. 9mm f2.7 - 1248mm f/3.5.) There are now some excellent
wide-angle and telephoto (tel-extender) add-on lenses for many makes and models
of P&S cameras. Add either or both of these small additions to your photography
gear and, with some of the new super-zoom P&S cameras, you can far surpass any
range of focal-lengths and apertures that are available or will ever be made for
larger format cameras.
2. P&S cameras can have much wider apertures at longer focal lengths than any
DSLR glass in existence. (E.g. 549mm f/2.4 and 1248mm f/3.5) when used with
high-quality tel-extenders, which by the way, do not reduce the lens' original
aperture one bit. Only DSLRs suffer from that problem due to the manner in which
their tele-converters work. They can also have higher quality full-frame
180-degree circular fisheye and intermediate super-wide-angle views than any
DSLR and its glass in existence. Some excellent fish-eye adapters can be added
to your P&S camera which do not impart any chromatic-aberration nor
edge-softness. When used with a super-zoom P&S camera this allows you to
seamlessly go from as wide as a 9mm (or even wider) 35mm equivalent focal-length
up to the wide-angle setting of the camera's own lens.
3. P&S smaller sensor cameras can and do have wider dynamic range than larger
sensor cameras E.g. a 1/2.5" sized sensor can have a 10.3EV Dynamic Range vs. an
APS-C's typical 7.0-8.0EV Dynamic Range. One quick example:
http://farm4.static.flickr.com/3142/2861257547_9a7ceaf3a1_o.jpg
4. P&S cameras are cost efficient. Due to the smaller (but excellent) sensors
used in many of them today, the lenses for these cameras are much smaller.
Smaller lenses are easier to manufacture to exacting curvatures and are more
easily corrected for aberrations than larger glass used for DSLRs. This also
allows them to perform better at all apertures rather than DSLR glass which is
only good for one aperture setting per lens. Side by side tests prove that P&S
glass can out-resolve even the best DSLR glass ever made. After all is said and
done, you will spend 1/4th to 1/50th the price that you would have to in order
to get comparable performance in a DSLR camera. When you buy a DSLR you are
investing in a body that will require expensive lenses, hand-grips, external
flash units, heavy tripods, more expensive larger filters, etc. etc. The
outrageous costs of owning a DSLR add up fast after that initial DSLR body
purchase. Camera companies count on this, all the way to their banks.
5. P&S cameras are lightweight and convenient. With just one P&S camera plus one
small wide-angle adapter and one small telephoto adapter weighing just a couple
pounds, you have the same amount of zoom range as would require over 10 to 20
pounds of DSLR body and lenses. You can carry the whole P&S kit in one roomy
pocket of a wind-breaker or jacket. The DSLR kit would require a sturdy
backpack. You also don't require a massive tripod. Large tripods are required to
stabilize the heavy and unbalanced mass of the larger DSLR and its massive
lenses. A P&S camera, being so light, can be used on some of the most
inexpensive, compact, and lightweight tripods with excellent results.
6. P&S cameras are silent. For the more common snap-shooter/photographer, you
will not be barred from using your camera at public events, stage-performances,
and ceremonies. Or when trying to capture candid shots, you won't so easily
alert all those within a block around, from the obnoxious noise that your DSLR
is making, that you are capturing anyone's images. For the more dedicated
wildlife photographer a P&S camera will not endanger your life when
photographing potentially dangerous animals by alerting them to your presence.
7. Some P&S cameras can run the revolutionary CHDK software on them, which
allows for lightning-fast motion detection (literally, lightning fast 45ms
response time, able to capture lightning strikes automatically) so that you may
capture more elusive and shy animals (in still-frame and video) where any
evidence of your presence at all might prevent their appearance. Without the
need of carrying a tethered laptop along or any other hardware into remote
areas--which only limits your range, distance, and time allotted for bringing
back that one-of-a-kind image. It also allows for unattended time-lapse
photography for days and weeks at a time, so that you may capture those unusual
or intriguing subject-studies in nature. E.g. a rare slime-mold's propagation,
that you happened to find in a mountain-ravine, 10-days hike from the nearest
laptop or other time-lapse hardware. (The wealth of astounding new features that
CHDK brings to the creative-table of photography are too extensive to begin to
list them all here. See http://chdk.wikia.com/wiki/CHDK )
8. P&S cameras can have shutter speeds up to 1/40,000th of a second. See:
http://chdk.wikia.com/wiki/CameraFeatures Allowing you to capture fast subject
motion in nature (e.g. insect and hummingbird wings) WITHOUT the need of
artificial and image destroying flash, using available light alone. Nor will
their wing shapes be unnaturally distorted from the focal-plane shutter
distortions imparted in any fast moving objects, as when photographed with all
DSLRs. (See focal-plane-shutter-distortions example-image link in #10.)
9. P&S cameras can have full-frame flash-sync up to and including shutter-speeds
of 1/40,000th of a second. E.g.
http://chdk.wikia.com/wiki/Samples:_High-Speed_Shutter_%26_Flash-Sync without
the use of any expensive and specialized focal-plane shutter flash-units that
must strobe for the full duration of the shutter's curtain to pass over the
frame. The other downside to those kinds of flash units, is that the
light-output is greatly reduced the faster the shutter speed. Any shutter speed
used that is faster than your camera's X-Sync speed is cutting off some of the
flash output. Not so when using a leaf-shutter. The full intensity of the flash
is recorded no matter the shutter speed used. Unless, as in the case of CHDK
capable cameras where the camera's shutter speed can even be faster than the
lightning-fast single burst from a flash unit. E.g. If the flash's duration is
1/10,000 of a second, and your CHDK camera's shutter is set to 1/20,000 of a
second, then it will only record half of that flash output. P&S cameras also
don't require any expensive and dedicated external flash unit. Any of them may
be used with any flash unit made by using an inexpensive slave-trigger that can
compensate for any automated pre-flash conditions. Example:
http://www.adorama.com/SZ23504.html
10. P&S cameras do not suffer from focal-plane shutter drawbacks and
limitations. Causing camera shake, moving-subject image distortions
(focal-plane-shutter distortions, e.g.
http://images3.wikia.nocookie.net/chdk/images//4/46/Focalplane_shutter_distortions.jpg
do note the distorted tail-rotor too and its shadow on the ground, 90-degrees
from one another), last-century-slow flash-sync, obnoxiously loud slapping
mirrors and shutter curtains, shorter mechanical life, easily damaged, expensive
repair costs, etc.
11. When doing wildlife photography in remote and rugged areas and harsh
environments, or even when the amateur snap-shooter is trying to take their
vacation photos on a beach or dusty intersection on some city street, you're not
worrying about trying to change lenses in time to get that shot (fewer missed
shots), dropping one in the mud, lake, surf, or on concrete while you do, and
not worrying about ruining all the rest of your photos that day from having
gotten dust & crud on the sensor. For the adventurous photographer you're no
longer weighed down by many many extra pounds of unneeded glass, allowing you to
carry more of the important supplies, like food and water, allowing you to trek
much further than you've ever been able to travel before with your old D/SLR
bricks.
12. Smaller sensors and the larger apertures available allow for the deep DOF
required for excellent macro-photography, WITHOUT the need of any image
destroying, subject irritating, natural-look destroying flash. No DSLR on the
planet can compare in the quality of available-light macro photography that can
be accomplished with nearly any smaller-sensor P&S camera.
13. P&S cameras include video, and some even provide for CD-quality stereo audio
recordings, so that you might capture those rare events in nature where a
still-frame alone could never prove all those "scientists" wrong. E.g. recording
the paw-drumming communication patterns of eusocial-living field-mice. With your
P&S video-capable camera in your pocket you won't miss that once-in-a-lifetime
chance to record some unexpected event, like the passage of a bright meteor in
the sky in daytime, a mid-air explosion, or any other newsworthy event. Imagine
the gaping hole in our history of the Hindenberg if there were no film cameras
there at the time. The mystery of how it exploded would have never been solved.
Or the amateur 8mm film of the shooting of President Kennedy. Your video-ready
P&S camera being with you all the time might capture something that will be a
valuable part of human history one day.
14. P&S cameras have 100% viewfinder coverage that exactly matches your final
image. No important bits lost, and no chance of ruining your composition by
trying to "guess" what will show up in the final image. With the ability to
overlay live RGB-histograms, and under/over-exposure area alerts (and dozens of
other important shooting data) directly on your electronic viewfinder display
you are also not going to guess if your exposure might be right this time. Nor
do you have to remove your eye from the view of your subject to check some
external LCD histogram display, ruining your chances of getting that perfect
shot when it happens.
15. P&S cameras can and do focus in lower-light (which is common in natural
settings) than any DSLRs in existence, due to electronic viewfinders and sensors
that can be increased in gain for framing and focusing purposes as light-levels
drop. Some P&S cameras can even take images (AND videos) in total darkness by
using IR illumination alone. (See: Sony) No other multi-purpose cameras are
capable of taking still-frame and videos of nocturnal wildlife as easily nor as
well. Shooting videos and still-frames of nocturnal animals in the total-dark,
without disturbing their natural behavior by the use of flash, from 90 ft. away
with a 549mm f/2.4 lens is not only possible, it's been done, many times, by
myself. (An interesting and true story: one wildlife photographer was nearly
stomped to death by an irate moose that attacked where it saw his camera's flash
come from.)
16. Without the need to use flash in all situations, and a P&S's nearly 100%
silent operation, you are not disturbing your wildlife, neither scaring it away
nor changing their natural behavior with your existence. Nor, as previously
mentioned, drawing its defensive behavior in your direction. You are recording
nature as it is, and should be, not some artificial human-changed distortion of
reality and nature.
17. Nature photography requires that the image be captured with the greatest
degree of accuracy possible. NO focal-plane shutter in existence, with its
inherent focal-plane-shutter distortions imparted on any moving subject will
EVER capture any moving subject in nature 100% accurately. A leaf-shutter or
electronic shutter, as is found in ALL P&S cameras, will capture your moving
subject in nature with 100% accuracy. Your P&S photography will no longer lead a
biologist nor other scientist down another DSLR-distorted path of non-reality.
18. Some P&S cameras have shutter-lag times that are even shorter than all the
popular DSLRs, due to the fact that they don't have to move those agonizingly
slow and loud mirrors and shutter curtains in time before the shot is recorded.
In the hands of an experienced photographer that will always rely on prefocusing
their camera, there is no hit & miss auto-focusing that happens on all
auto-focus systems, DSLRs included. This allows you to take advantage of the
faster shutter response times of P&S cameras. Any pro worth his salt knows that
if you really want to get every shot, you don't depend on automatic anything in
any camera.
19. An electronic viewfinder, as exists in all P&S cameras, can accurately relay
the camera's shutter-speed in real-time. Giving you a 100% accurate preview of
what your final subject is going to look like when shot at 3 seconds or
1/20,000th of a second. Your soft waterfall effects, or the crisp sharp outlines
of your stopped-motion hummingbird wings will be 100% accurately depicted in
your viewfinder before you even record the shot. What you see in a P&S camera is
truly what you get. You won't have to guess in advance at what shutter speed to
use to obtain those artistic effects or those scientifically accurate nature
studies that you require or that your client requires. When testing CHDK P&S
cameras that could have shutter speeds as fast as 1/40,000th of a second, I was
amazed that I could half-depress the shutter and watch in the viewfinder as a
Dremel-Drill's 30,000 rpm rotating disk was stopped in crisp detail in real
time, without ever having taken an example shot yet. Similarly true when
lowering shutter speeds for milky-water effects when shooting rapids and falls,
instantly seeing the effect in your viewfinder. Poor DSLR-trolls will never
realize what they are missing with their anciently slow focal-plane shutters and
wholly inaccurate optical viewfinders.
20. P&S cameras can obtain the very same bokeh (out of focus foreground and
background) as any DSLR by just increasing your focal length, through use of its
own built-in super-zoom lens or attaching a high-quality telextender on the
front. Just back up from your subject more than you usually would with a DSLR.
Framing and the included background is relative to the subject at the time and
has nothing at all to do with the kind of camera and lens in use. Your f/ratio
(which determines your depth-of-field), is a computation of focal-length divided
by aperture diameter. Increase the focal-length and you make your DOF shallower.
No different than opening up the aperture to accomplish the same. The two
methods are identically related where DOF is concerned.
21. P&S cameras will have perfectly fine noise-free images at lower ISOs with
just as much resolution as any DSLR camera. Experienced Pros grew up on ISO25
and ISO64 film all their lives. They won't even care if their P&S camera can't
go above ISO400 without noise. An added bonus is that the P&S camera can have
larger apertures at longer focal-lengths than any DSLR in existence. The time
when you really need a fast lens to prevent camera-shake that gets amplified at
those focal-lengths. Even at low ISOs you can take perfectly fine hand-held
images at super-zoom settings. Whereas the DSLR, with its very small apertures
at long focal lengths require ISOs above 3200 to obtain the same results. They
need high ISOs, you don't. If you really require low-noise high ISOs, there are
some excellent models of Fuji P&S cameras that do have noise-free images up to
ISO1600 and more.
22. Don't for one minute think that the price of your camera will in any way
determine the quality of your photography. Any of the newer cameras of around
$100 or more are plenty good for nearly any talented photographer today. IF they
have talent to begin with. A REAL pro can take an award winning photograph with
a cardboard Brownie Box camera made a century ago. If you can't take excellent
photos on a P&S camera then you won't be able to get good photos on a DSLR
either. Never blame your inability to obtain a good photograph on the kind of
camera that you own. Those who claim they NEED a DSLR are only fooling
themselves and all others. These are the same people that buy a new camera every
year, each time thinking, "Oh, if I only had the right camera, a better camera,
better lenses, faster lenses, then I will be a great photographer!" Camera
company's love these people. They'll never be able to get a camera that will
make their photography better, because they never were a good photographer to
begin with. The irony is that by them thinking that they only need to throw
money at the problem, they'll never look in the mirror to see what the real
problem is. They'll NEVER become good photographers. Perhaps this is why these
self-proclaimed "pros" hate P&S cameras so much. P&S cameras instantly reveal to
them their piss-poor photography skills.
23. Have you ever had the fun of showing some of your exceptional P&S
photography to some self-proclaimed "Pro" who uses $30,000 worth of camera gear.
They are so impressed that they must know how you did it. You smile and tell
them, "Oh, I just use a $150 P&S camera." Don't you just love the look on their
face? A half-life of self-doubt, the realization of all that lost money, and a
sadness just courses through every fiber of their being. Wondering why they
can't get photographs as good after they spent all that time and money. Get good
on your P&S camera and you too can enjoy this fun experience.
24. Did we mention portability yet? I think we did, but it is worth mentioning
the importance of this a few times. A camera in your pocket that is instantly
ready to get any shot during any part of the day will get more award-winning
photographs than that DSLR gear that's sitting back at home, collecting dust,
and waiting to be loaded up into that expensive back-pack or camera bag, hoping
that you'll lug it around again some day.
25. A good P&S camera is a good theft deterrent. When traveling you are not
advertising to the world that you are carrying $20,000 around with you. That's
like having a sign on your back saying, "PLEASE MUG ME! I'M THIS STUPID AND I
DESERVE IT!" Keep a small P&S camera in your pocket and only take it out when
needed. You'll have a better chance of returning home with all your photos. And
should you accidentally lose your P&S camera you're not out $20,000. They are
inexpensive to replace.
There are many more reasons to add to this list but this should be more than
enough for even the most unaware person to realize that P&S cameras are just
better, all around. No doubt about it.
The phenomenon of everyone yelling "You NEED a DSLR!" can be summed up in just
one short phrase:
"If even 5 billion people are saying and doing a foolish thing, it remains a
foolish thing."
Steve
>>speed can also influence the cycle time, adding another delay. All
>>this means that "Live View" is actually delayed view. Often this
>>delay is longer than 100 milliseconds, and that means when you
>>press the shutter the subject is in a slightly different position
>>than what you see on the LCD screen. This is another factor in fast
>>action photography and why those who do such photography usually choose
>>an optical viewfinder. But it is not the main factor. The main factor
>>is predictive autofocus.
>
>LOL!! He doesn't even know how to use live-view nor how it works. The only "lag"
>is the EVF/LCD refresh rate, which is 60 to 120 fps or faster. The live-view is
Thank you for revealing once again that when it comes to the real
facts about cameras, you have no idea what you're talking about.
You can see the effects of live view lag on high pixel count cameras
easily, and it's much greater than the LCD refresh rate. Just point
the camera at something and then move sharply and you'll see the
movement on the LCD image is delayed from when you actually moved the
camera.
This delay is so low as to be not noticable with my old 4MP P&S. But
I just tried it in Best Buy with a whole slew of 10MP P&S and even the
live view on two DSLRs and the delay is noticable to some degree or
another.
Steve
Paul
message news:4913C112...@qwest.net...
> Here is a demonstration of autofocus tracking of a DSLR:
> http://www.clarkvision.com/photoinfo/tracking.action.with.autofocus
You mentioned the possibility of autofocus shifting to the background with a
busy background. On a 20D this sometimes happens to me even with a plain
sky when tracking fast moving jets (and the AF point moved off the subject
very briefly). Even more annoyingly, with a plain sky there is nothing for
the AF to focus on and so the lens just hunts and you loose the shot.
Surely cameras now-a-days should be intelligent enough to know that if you
have been tracking a subject for a few seconds, that this is the subject you
are trying to photograph and therefore shouldn't be so quick to try and
focus on something else?
You also mentioned the AF shifting to the foreground in the case where you
came between your friend and the eagle. I have also experienced this too
and is similar to the above situation. Why should AF think that you
suddenly want to shift focus to the foreground, when you have already been
tracking the subject for a few seconds?
In the last scenario, with custom functions it is possible to change the AE
button to stop/start AF when you press the button (if for example you are
panning and know that there is a subject (such as a tree) coming up between
you and what you are photographing). Of course, this takes a bit of getting
used to and is not ideal. However, I thought that CF.20 on the 1D series
allowed you to change the sensitivity of the AI Servo tracking, so that for
sports shooters where it's not uncommon for a referee/another player to run
between you and your subject (or in the case of your friend, you coming
between the bird and him), it delays shifting focus so quickly. Maybe the
'slow' sensitivity setting should be longer than 1 second before shifting
focus? Or, maybe there should be a CF that you can turn on that tells the
camera that if you are tracking a subject for more than say a couple of
seconds, that this is what you are trying to photograph and not shift focus
to something else? With scene recognition/colour pattern tracking, surely
it is possible for the camera to recognise what you are tracking? Afterall,
if you want to focus on something else, you would let go of the button and
pick up focus again.
It would be interesting to know if Nikons 3D system prevents the above 2
mentioned problems. I've just looked on Google briefly and if appears to
use colour recognition in it's 3D focus tracking system:
http://kammagamma.com/articles/nikons-new-3d-51-points-dynamic-af.php
I am also wondering if it's possible to focus and recompose with the Nikon
3D system and it will track the area that you took the initial focus from?
So for example, in a portrait you focus on an eye with the centre point,
recompose and the camera tracks where the eye is and keeps it in focus. Or
in your situation with the bird, you focus on the head with the centre point
and if you recompose whilst still tracking, it will keep focus on the head
and ignore the wings, etc.
Roy G
"Hank Thomas" <hankt...@ipt.aol.org> wrote in message
news:2ae8h4hogiv2vie7p...@4ax.com...
>
>
> LOL!!! The N.Clark spamming moron is BACK spewing his ignorance and
> stupidity
> again!!
>
> LOL
>
>
>photography to some self-proclaimed >"Pro" who uses $30,000 worth of camera
>gear.
>They are so impressed that they must know how you did >it.
We keep asking to see some of your photos.
Put up or shut up.
Roy G
SylvanA
LOL
Thanks for CONFIRMING that you don't know what you are talking about. Re-read
this, paying particular attention to the second paragraph. This now proves just
how unaware and unperceptive that you are. I'd hate to see your photography
after knowing this. There appears to be a mismatch between your eyes and your
brain. I'd have that checked out if I were you.
LOL
>On Wed, 05 Nov 2008 23:24:20 GMT, "Dudley Hanks"
><photos....@dudley-hanks.com> wrote:
>
>> Live View drag
>
>This is such a huge misnomer. There really is no such thing as "live view drag"
>in any camera with an EVF/LCD system these days. A true live-view delay will
>never be more than about 1/60th of a second, and in many cameras much faster
>than that as a minimum, far shorter than any human perception. This is the
>refresh rate of the EVF/LCD display.
>
>What you are experiencing as "live view drag" is the live-view recreating the
>shutter-speed in real time. This is how an EVF/LCD viewfinder is able to
>accurately represent those soft moving-water effects at slow shutter speeds and
>stop-motion flapping bird wing images at high shutter speeds. The reason this
>"live-view drag" has become a mantra of those with less experience is that they
>test their P&S camera in the store. Never once realizing that the slower shutter
>speed used indoors is what causes this perceived "live view drag".
>
>For the experienced/advanced photographer that has come to understand the vast
>benefits they wouldn't buy any camera without this feature. Having what you call
>this "live view drag" is even more important to someone like me than being able
>to use a bright DOF preview (as also exists on all P&S cameras). I want to
>instantly see what happens to the final capture of my moving subjects as I
>change shutter speeds. I enjoy having that instantaneous film-to-print preview
>in real-time as I frame my shots.
>
>D-SLR owners who have never had this great feature all their lives won't
>recognize it for what it is, nor will they understand how to make use of it.
>They at first, wrongly and ignorantly, consider this some kind of drawback
>instead of the great asset that it is. Until they finally learn on their own.
>This is why "live view" is becoming more commonplace in D-SLRs, to slowly
>introduce them to the vast benefits that P&S cameras have had for a decade.
>
>The mindless D-SLR owner/buyer/promoter will eventually figure it out, one day.
>But then, come to think of it, the D-SLR owner lost use of something as simple
>as having a bright DOF preview (as used to exist in better SLRs of the past, and
>still exists on all P&S cameras). They don't consider that any great loss nor
>even realize why its important. Some will just never figure it out.
Don Stauffer
>
> Why do DSLR's still use mirrors?
Simple. If it didn't have a mirror (or surface that acts like a mirror)
it wouldn't be a single lens REFLEX. The term reflex means it has a
mirror in the viewfinding train. This is true film OR digital.
Note that a "twin lens reflex" also generally has a 45 degree folding
mirror also.
corey-anderson
>"Roger N. Clark (change username to rnclark)" <user...@qwest.net> wrote in
>message news:4913C112...@qwest.net...
>
>> Here is a demonstration of autofocus tracking of a DSLR:
>> http://www.spamlink.com/photoinfo/tracking.action.with.autofocus
Thanks for giving excellent examples of why no REAL pro in the world would
depend on auto-focusing for anything on any camera. Thousands upon thousands of
missed shots in your life-time.
:-)
Those who want to rely on a point-and-shoot auto-focus feature of their DSLR and
praise what a wonderful feature it is, is only revealing their sub-amateur
status as any kind of photographer. They love to kid themselves with what they
bought. Oh, if they could only buy a camera that will do everything for them,
they might actually be a photographer one day. They can only keep hoping. LOL
Alfred Molon
>
> You can see the effects of live view lag on high pixel count cameras
> easily, and it's much greater than the LCD refresh rate.
It's not. I have two live view cameras (Olympus 8080 and Sony R1) which
have no noticeable delay in live view.
> Just point
> the camera at something and then move sharply and you'll see the
> movement on the LCD image is delayed from when you actually moved the
> camera.
Only a few cameras have a feature which simulates the shutter lag, but
you can turn that off.
--
Alfred Molon
------------------------------
Olympus 50X0, 8080, E3X0, E4X0, E5X0 and E3 forum at
http://tech.groups.yahoo.com/group/MyOlympus/
http://myolympus.org/ photo sharing site
Jürgen Exner
>Why do DSLR's still use mirrors?
Because without a mirror it would be a dSL without the R.
jue
Alfred Molon
to rnclark) says...
> Many cameras have what is called "Live View." Live view is an electronic
> method of reading the "digital" sensor and displaying the result on
> an LCD screen. The term "Live View" is a misnomer. It takes time
> to read out the sensor, and the more pixels the sensor has, the more
> time it takes. Very high speed electronics in high end cameras can
> read out at rates of around 100 million pixels per second. On a
> 10-megapixel camera, that means the time to read out is about 1/10th
> second (100 milliseconds).
Then how come frame refresh rates even on cheap DSLRs are way higher
than 10 per second?
> On lower cost cameras, slower
> electronics are used, so the readout times can be longer. It also
> takes time to send that data to the LCD. On some cameras, the shutter
> speed can also influence the cycle time, adding another delay. All
> this means that "Live View" is actually delayed view. Often this
> delay is longer than 100 milliseconds, and that means when you
> press the shutter the subject is in a slightly different position
> than what you see on the LCD screen. This is another factor in fast
> action photography and why those who do such photography usually choose
> an optical viewfinder. But it is not the main factor. The main factor
> is predictive autofocus.
For practical purposes the delay is so small as not to matter - at least
for the P&S cameras I've been using.
The only issue with P&S is that AF can be quite slow in some situations.
> P&S cameras, especially small cheaper ones use the sensor for autofocus
> using a contrast detection method. The lens is moved, the sensor read out,
> and the contrast checked, the lens moved, the sensor read out, the
> contrast checked and if it is getting better keep moving in that direction,
> if not, go back, hunting for best focus.
The new Panasonic micro 4/3 seems to substantially better for what
concerns AF.
SMS
> Bottom line: if you want to take photographs of things in action that
> may be moving toward or away from the camera, choose a camera with
> predictive autofocus. All DSLRs that I know of have predictive
> autofocus. I do not know any P&S cameras with predictive autofocus.
Thanks Roger, but I think this all went over the head of our favorite troll.
What's really amazing is that professionals nearly always use auto-focus
because the auto-focus on D-SLRs is so fast and so accurate.
BTW, Ricoh used to have an extremely fast hybrid autofocus system that
combined contrast detection focusing on the CCD with an external passive
AF sensor for phase-detection auto-focus. No more. It was very expensive
to implement, and with the prosumers and professionals all moving to
D-SLRs, there was no market for such an expensive P&S. OTOH, many of the
D-SLRs now offer the choice of contrast detection during live-view, or
phase detection when using the viewfinder.
David J Taylor
> In article <4913C112...@qwest.net>, Roger N. Clark (change
> username to rnclark) says...
>
>> Many cameras have what is called "Live View." Live view is an
>> electronic method of reading the "digital" sensor and displaying the
>> result on
>> an LCD screen. The term "Live View" is a misnomer. It takes time
>> to read out the sensor, and the more pixels the sensor has, the more
>> time it takes. Very high speed electronics in high end cameras can
>> read out at rates of around 100 million pixels per second. On a
>> 10-megapixel camera, that means the time to read out is about 1/10th
>> second (100 milliseconds).
>
> Then how come frame refresh rates even on cheap DSLRs are way higher
> than 10 per second?
It depend how many pixels are read out. For live view display, you may
only need 300K-900K pixels, and not the full 10MP. But any live-view
system, be it DSLR or compact, will have a delay, and the user may need to
learn to live with that delay and compensate for it.
David
David J Taylor
> In article <1sg8h4d0ni1c1saua...@4ax.com>, Steve says...
>>
>> You can see the effects of live view lag on high pixel count cameras
>> easily, and it's much greater than the LCD refresh rate.
>
> It's not. I have two live view cameras (Olympus 8080 and Sony R1)
> which have no noticeable delay in live view.
>
>> Just point
>> the camera at something and then move sharply and you'll see the
>> movement on the LCD image is delayed from when you actually moved the
>> camera.
>
> Only a few cameras have a feature which simulates the shutter lag, but
> you can turn that off.
This isn't an emulation, Alfred, this is a delay between the sensing and
the display of the image. I've seen this in may compact cameras, and it's
most noticeable at low ambient light levels when the image from the sensor
has to have an exposure of a significant fraction of a second. It seems
that some compact cameras integrate the image either on the sensor or
between sensor and display to produce an acceptable display in these
low-light conditions. The lag is then very noticeable.
David
Harlan Adams
>Thanks Roger, but I think this all went over the head of our favorite troll.
Many points outlined below completely disprove your usual resident-troll
bullshit. You can either read it and educate yourself, or don't read it and
continue to prove to everyone that you are nothing but a virtual-photographer
newsgroup-troll and a fool.
23. Have you ever had the fun of showing some of your exceptional P&S
photography to some self-proclaimed "Pro" who uses $30,000 worth of camera gear.
Alan Browne
> On Thu, 06 Nov 2008 21:16:18 -0700, "Roger N. Clark (change username
> to rnclark)" <user...@qwest.net> wrote:
>
>> Test your shutter lag in your camera at:
>> http://www.shooting-digital.com/columns/schwartz/shutter_release_test/default.asp
On Safari and Firefox (Mac) the arrow hesitates passing through 0, so
better to test from the 1 at the bottom...
--
-- r.p.e.35mm user resource: http://www.aliasimages.com/rpe35mmur.htm
-- r.p.d.slr-systems: http://www.aliasimages.com/rpdslrsysur.htm
-- [SI] gallery & rulz: http://www.pbase.com/shootin
-- e-meil: Remove FreeLunch.
-- usenet posts from gmail.com and googlemail.com are filtered out.
David J Taylor
> Eric Stevens wrote:
>> On Thu, 06 Nov 2008 21:16:18 -0700, "Roger N. Clark (change username
>> to rnclark)" <user...@qwest.net> wrote:
>>
>>> Test your shutter lag in your camera at:
>>> http://www.shooting-digital.com/columns/schwartz/shutter_release_test/default.asp
>
> On Safari and Firefox (Mac) the arrow hesitates passing through 0, so
> better to test from the 1 at the bottom...
It does that with Firefox and MS Internet Explorer on a PC as well. I
wonder if that's a deliberate built-in delay to allow for human reaction
time? Or just a fault in the Adobe Flash player?
David
franko
You missed some important information (reposted below). Without this information
in your mind you keep appearing to be nothing but another of the many
virtual-photographer (or sub-amateur) trolls around here.
SMS
> Test your shutter lag in your camera at:
> http://www.shooting-digital.com/columns/schwartz/shutter_release_test/default.asp
Cool site.
With prefocus, my SD800 IS is about 0.15 seconds. Without pre-focus it's
0.4 seconds.
With prefocus, my D-SLR is 0.09 seconds. Without prefocus it's 0.22 seconds.
If I changed lenses the D-SLR would probably be faster, it didn't like
focusing on the computer screen with the 10-22 EF-s
Professional testing of the same cameras shows the D-SLR doing full
auto-focus at 0.15 seconds, and 0.077 seconds for pre-focus, and shows
the SD800 IS at 0.4 seconds for full auto-focus.
So it's true that by doing pre-focus on a P&S, you can get about the
same performance as a D-SLR in full auto-focus, but of course you can't
even come close to a D-SLR that's pre-focused, the P&S is twice as slow.
jdear64
> On Fri, 07 Nov 2008 07:22:54 -0800, SMS <scharf.ste...@geemail.com> wrote:
> >Thanks Roger, but I think this all went over the head of our favorite troll.
>
> Many points outlined below completely disprove your usual resident-troll
> bullshit.
<snip>
Wow, so many posters with exactly the same view point, spelling, and
writing
style as yourself.
You must be one of the loneliest losers on usenet to have to resort to
so many
sock puppets. I pity your lack of life.
TrayJohnson
Not the same, the P&S is faster. And you are an outright liar if you think that
the time needed to move that noisy, image-jarring, and slapping mirror out of
the way, opening up that noisy and slow focal-plane shutter are in any way going
to be faster when both are prefocused. How transparently deceptive you are. You
also reveal that you don't know that contrast-focusing is much faster if the
image is steady and a higher-shutter speed is used. If you can hold the camera
steady with a 400mm lens then it is just as fast at focusing as at wide-angle.
All those the financially-biased owners of those "professional testing" sites
online don't even know how to hold a camera steady. As proved by their really
poor results when testing image-stabilization methods. They reveal much in their
tests, much that they wish a more intelligent and perceptive person wouldn't
notice. Namely, that they are really bad photographers who don't even know how
to use a camera properly.
It would help too if you actually bought some decent cameras. But then, now
would you know what is or is not a decent camera. You've made it quite obvious
that you never could figure that one out.
You really should read the following, you just keep making an even bigger fool
of yourself.
ZamphorBiggins
And this discounts the truth of what has been posted, how? Oh, that's right. You
think that you need 1 million people to say the same thing before it should be
believed. Just like any mindless non-thinking follower.
Do try to stay on topic. If this is the only way you can discount some facts I
truly pity your lack of intellect.
If only everyone discounted Einstein for being the only one to post "E=MC^2" all
those years ago, we'd be much better off just because everyone wasn't saying it.
Granted, the information here is not as ground-breaking (because any fool in his
right mind can see the truthfulness of the P&S's superiority), but the analogy
still holds true.
Holy fuck, you are one major idiot.
SMS
> On Nov 7, 7:44 am, Harlan Adams <had...@addressdeleted.com> wrote:
>> On Fri, 07 Nov 2008 07:22:54 -0800, SMS <scharf.ste...@geemail.com> wrote:
>>> Thanks Roger, but I think this all went over the head of our favorite troll.
>> Many points outlined below completely disprove your usual resident-troll
>> bullshit.
> You must be one of the loneliest losers on usenet to have to resort to
> so many sock puppets. I pity your lack of life.
LOL, he may not know anything about photographic equipment, but he sure
is good at forging identities really quickly!
While I feel bad for him too, it got old after a while, and he had to be
eliminated. He reminds me of the old "George Preddy" character on this
group. No knowledge, but that didn't stop him from being his own little
sock-puppet. Thank goodness the Sigma crap is over. Amazingly, Consumer
Reports included the Sigma SD14 in their D-SLR review, and rated it
"Lowest" for image quality.
Alan Browne
Not sure. Probably a series of images that plays once and re-starts and
that's where it hesitates, on each re-start.
Would be more effective as an executable DL.
If you have a stopwatch timer on your computer you could run that and
then depress the shutter as it goes through each second. Do 5 in a row
(say every 2 or 3 seconds) and then take the stats from the images...
Alan Browne
Did you notice if the clock is hesitating going through 0 on your
machine? That shortens the measurement by over 0.05s on mine.
If so then re-do those off of the bottom of the clock (1 second mark).
The timer above hesitates going through 0 (my Mac, 2 browsers; David
Taylor too on PC with another browser).
AF is going to suffer as it sees the scan flicker invisible to us.
Alan Browne
> LOL, he may not know anything about photographic equipment, but he sure
> is good at forging identities really quickly!
Stop feeding it.
SMS
> If you have a stopwatch timer on your computer you could run that and
> then depress the shutter as it goes through each second. Do 5 in a row
> (say every 2 or 3 seconds) and then take the stats from the images...
The results I got were very close to the published tests by
professionals, so that program does work pretty well.
It was kind of cool to see how long the shutter stayed open to
compensate for the low light, you can see the arrow as if it was in
time-lapse.
In any case, it only verified what everyone already knew--the auto-focus
on D-SLRs is much much faster.
Alxe B. Farnsworth
He can't help it. Even though he claims he's filtered out on 4ax domains, I
already proved to him how stupid that was, so I reinstated that domain, which
can only means he sees everything again. He knows he's wrong and wants me to
keep posting the following info. Don't your realize when you've been trolled by
a resident-troll? I do. But I'm smart enough to use it to my advantage.
(resident trolls, like yourself, are never too bright)
Alan Browne
> Alan Browne wrote:
>
>> If you have a stopwatch timer on your computer you could run that and
>> then depress the shutter as it goes through each second. Do 5 in a
>> row (say every 2 or 3 seconds) and then take the stats from the images...
>
> The results I got were very close to the published tests by
> professionals, so that program does work pretty well.
That's what I was asking: do you see it hesitate at the top?
If not, fine.
But David T and I see it hesitate. The stats I get from the 0 and the
stats I get from the 1 mark differ by 50ms or so...
Me Here
"Jürgen Exner" <jurg...@hotmail.com> wrote in message
news:umm8h45hi8gdrfndt...@4ax.com...
Yet Consumer Reports calls the Panasonic G1 a dSLR, gives them no credence..
Me Here
"ZamphorBiggins" <zbig...@noaddress.gov> wrote in message
news:5ou8h4tl00nu7qfie...@4ax.com...
> On Fri, 7 Nov 2008 09:22:20 -0800 (PST), jdear64 <jde...@yahoo.com>
> wrote:
>
>>On Nov 7, 7:44 am, Harlan Adams <had...@addressdeleted.com> wrote:
>>> On Fri, 07 Nov 2008 07:22:54 -0800, SMS <scharf.ste...@geemail.com>
>>> wrote:
>>> >Thanks Roger, but I think this all went over the head of our favorite
>>> >troll.
>>>
>>> Many points outlined below completely disprove your usual resident-troll
>>> bullshit.
>>
>><snip>
>>
>>Wow, so many posters with exactly the same view point, spelling, and
>>writing
>>style as yourself.
>>
>>You must be one of the loneliest losers on usenet to have to resort to
>>so many
>>sock puppets. I pity your lack of life.
>
> And this discounts the truth of what has been posted, how? Oh, that's
> right. You
> think that you need 1 million people to say the same thing before it
> should be
> believed. Just like any mindless non-thinking follower.
>
too...
Alfred Molon
Taylor says...
As I wrote, you can turn this emulation off, if you choose to do so.
Alfred Molon
Taylor says...
> It depend how many pixels are read out. For live view display, you may
> only need 300K-900K pixels, and not the full 10MP. But any live-view
> system, be it DSLR or compact, will have a delay, and the user may need to
> learn to live with that delay and compensate for it.
For practical purposes that delay is insignificant.
Alfred Molon
says...
any camera with a large sensor and interchangeable lenses a DSLR.
Alfred Molon
> With prefocus, my D-SLR is 0.09 seconds.
Why not instant, i.e. what does your DSLR need those 90ms for? To move
the mirror away?
SMS
> In article <umm8h45hi8gdrfndt...@4ax.com>, Jürgen Exner
> says...
>> "Roger N. Clark (change username to rnclark)" <user...@qwest.net>
>> wrote:
>>> Why do DSLR's still use mirrors?
>> Because without a mirror it would be a dSL without the R.
>
> Most people probably don't know this fine distinction and would consider
> any camera with a large sensor and interchangeable lenses a DSLR.
This is true, even though it still has some of disadvantages of a P&S,
it at least has the larger sensor. Though if someone could make a ZLR
with a larger sensor, and a wide zoom range, it'd be better than the G1.
David J Taylor
Not on the cameras I was testing - there is no such emulation.
How much lag do you see in low-light, with the shutter speed set to, for
example, 1/1000s?
David
David J Taylor
> In article <_cZQk.84155$E41....@text.news.virginmedia.com>, David J
> Taylor says...
>
>> It depend how many pixels are read out. For live view display, you
>> may only need 300K-900K pixels, and not the full 10MP. But any
>> live-view system, be it DSLR or compact, will have a delay, and the
>> user may need to learn to live with that delay and compensate for it.
>
> For practical purposes that delay is insignificant.
Whether or not it is significant depends on the user, and the use to which
the camera is being put.
David
David J Taylor
They did - Sony made the R1 but it ended up having less zoom range, and
being a brute of a camera becuase of the size of the sensor. Did it sell?
David
WhoDat
You are apparently unaware of a few FACTS: read 'em and weep:
Nathan Grimwald
Oh, please do name ONE situation where the significance of where a P&S camera is
.00001 ms faster than a slower DSLR camera is significant. All eyes are upon
your self-deceptions, awaiting your felonious and psychotic repy. :-)
What trolls these DSLR fools be.
Alfred Molon
> This is true, even though it still has some of disadvantages of a P&S,
> it at least has the larger sensor. Though if someone could make a ZLR
> with a larger sensor, and a wide zoom range, it'd be better than the G1.
Well, with the G1 you have the advantage of being able to change the
lens. Usually lenses with a large zoom range are optically less good
than lenses with a smaller zoom range.
SMS
> They did - Sony made the R1 but it ended up having less zoom range, and
> being a brute of a camera becuase of the size of the sensor. Did it sell?
It runs into the same problems as all of these ZLRs. By the time you put
on the long lens, and in the case of the R1 the larger sensor, you're
just not saving much in manufacturing cost versus using a lens mount and
a mirror, plus you still have all the other disadvantages of the P&S to
contend with. You've saved no weight and no size, and very little money,
and you end up with decidedly inferior results compared to a D-SLR.
You often see inquiries as to why "they" can't make a D-SLR without
interchangeable lenses, just include a wide-range zoom like the 18-200
IS. But the cost of the lens mount and the electrical connection are
very low, so it would not result in much of a cost savings, and it
probably wouldn't sell very well so volumes would be low, increasing
manufacturing costs further. It's much better they way it's playing out
now, with D-SLR prices in free-fall. Too bad lens prices aren't
following that same trend!
David J Taylor
[]
> You often see inquiries as to why "they" can't make a D-SLR without
> interchangeable lenses, just include a wide-range zoom like the 18-200
> IS. But the cost of the lens mount and the electrical connection are
> very low, so it would not result in much of a cost savings, and it
> probably wouldn't sell very well so volumes would be low, increasing
> manufacturing costs further. It's much better they way it's playing
> out now, with D-SLR prices in free-fall. Too bad lens prices aren't
> following that same trend!
Well, you have to make your money /somewhere/!
<G>
David
SMS
That's true.
In fact I believe that one reason why we don't see better P&S models is
because they don't want to enable that part of the market. It made sense
when D-SLR bodies were so expensive that the high end P&S models sold
very well. Now there's little incentive for them to build a P&S with the
capabilities of a D-SLR. P&S are high-volume commodities sold to the
masses based on megapixels and LCD size, and then when the masses
complain about the P&S results they're told, 'well if you really care
about things like noise, low-light shooting, fast auto-focus, etc. then
we have a solution for you.' So they sell you a very capable, low cost
body and a couple of lenses, and maybe a flash, and they've made a lot
more money. It's not all that different from the days of film, but with
film you had some really good P&S film cameras, something that's not the
case now.
SMS
> In article <%E1Rk.4040$hc1....@flpi150.ffdc.sbc.com>, SMS says...
>
>> This is true, even though it still has some of disadvantages of a P&S,
>> it at least has the larger sensor. Though if someone could make a ZLR
>> with a larger sensor, and a wide zoom range, it'd be better than the G1.
>
> Well, with the G1 you have the advantage of being able to change the
> lens. Usually lenses with a large zoom range are optically less good
> than lenses with a smaller zoom range.
Yes that's true. Still, I can't imagine opting for the G1 versus the
smallest true D-SLR. The size and weight difference aren't all that
much, and the advantages of the D-SLR are significant.
TrollSpotter
>It runs into the same problems as all of these ZLRs. By the time you put
>on the long lens, and in the case of the R1 the larger sensor, you're
>just not saving much in manufacturing cost versus using a lens mount and
>a mirror, plus you still have all the other disadvantages of the P&S to
>contend with. You've saved no weight and no size, and very little money,
>and you end up with decidedly inferior results compared to a D-SLR.
Spoken like a true virtual-photographer troll who has zero experience in the
real world. There might be times where a f/.3.5 2000+mm focal length is needed.
Something that no DSLR in existence can attain. Check out this hand-held 2197mm
f/3.5 photograph taken with a P&S camera.
http://farm3.static.flickr.com/2124/2999210192_bc589b9887_o.jpg
Read it and weep:
Many points outlined below completely disprove your usual resident-troll
bullshit. You can either read it and educate yourself, or don't read it and
continue to prove to everyone that you are nothing but a virtual-photographer
newsgroup-troll and a fool.
CamptonCornwelll
What a shame that you haven't educated yourself.
arnold_ziffled
>In fact I believe that one reason why we don't see better P&S models is
>because they don't want to enable that part of the market.
Really? What a shame that you aren't up to date on current technology.
Steve
On Fri, 07 Nov 2008 08:47:34 -0600, corey-anderson
<cand...@removethistoreply.com> wrote:
>
>Thanks for giving excellent examples of why no REAL pro in the world would
>depend on auto-focusing for anything on any camera. Thousands upon thousands of
>missed shots in your life-time.
Thanks for again revealing that you have no idea what REAL pros do.
dj_nme
> Roger N. Clark (change username to rnclark) wrote:
>
>>
>> Why do DSLR's still use mirrors?
>
> it wouldn't be a single lens REFLEX. The term reflex means it has a
> mirror in the viewfinding train. This is true film OR digital.
>
> Note that a "twin lens reflex" also generally has a 45 degree folding
> mirror also.
The TLR (twin lens reflex) cameras which I've used or examined seem to
have a fixed mirror in the viewfinder.
It doesn't have to move out of the way, as does in a SLR camera.
They may have a folding hood for the focus screen or an interchangeable
viewfinder prism eyepiece or a peep-sight "sports finder" as accessories.
RichA
"Roger N. Clark (change username to rnclark)" <user...@qwest.net> wrote in
message news:4913C112...@qwest.net...
>I was asked to comment on P&S versus DSLRs. I only read a few
> posts to see things haven't changed much here. I didn't see
> a real answer so here is one major difference between DSLRs
> and P&S cameras that does not seem to have been discussed.
> ----
>
> Why do DSLR's still use mirrors? One answer is simple and due
> to the requirements of predictive autofocus and tracking of
> moving subjects. Predictive autofocus systems provide the fastest
> autofocus and fastest autofocus tracking technology currently
> available in consumer and professional cameras, both film and digital.
>
Things are changing. Test out the Panasonic G1.
Elmo von Thud
to rnclark)" <user...@qwest.net> wrote:
[sneep]
>Why do DSLR's still use mirrors?
[sneep]
I'll have to reflect upon that question b4 I can give you an answer.
Elmo
Alfred Molon
> Yes that's true. Still, I can't imagine opting for the G1 versus the
> smallest true D-SLR. The size and weight difference aren't all that
> much, and the advantages of the D-SLR are significant.
The only advantage would be the better AF and currently the wider choice
of lenses, since micro 4/3 is a new standard.
Otherwise the G1 has the following advantages:
- mechanically more robust because there is no swinging mirror
- no noise due to the swinging mirror (my A350 wakes up the dead)
- no front-focus or back-focus issues
- EVF showing 100% of the image
- zoomable EVF with image information (histogram etc.)
- no misalignment between EVF and image sensor possible
- I would also expect better vignetting performance, since the lenses of
the G1 will be designed from the start for digital cameras and are
closer to the sensor. Most lenses of DLSRs have a lot of vignetting.
- and obviously the more compact size
Alfred Molon
Taylor says...
> How much lag do you see in low-light, with the shutter speed set to, for
> example, 1/1000s?
In that case you see no shutter lag (well, I can speak for the Olympus
8080 and Sony R1).
Alfred Molon
Taylor says...
> Alfred Molon wrote:
> > For practical purposes that delay is insignificant.
>
> Whether or not it is significant depends on the user, and the use to which
> the camera is being put.
Even if there was a delay of 100ms, there are not many situations where
that would matter (even people can't manage to move a lot in 1/10s). But
more likely the delay is below 100ms.
Alfred Molon
Taylor says...
> They did - Sony made the R1 but it ended up having less zoom range, and
> being a brute of a camera becuase of the size of the sensor. Did it sell?
I bought it and can tell you that it's a fine camera. The only problem
is that the sensor Sony chose was not that good at high ISO and that for
practical purposes there was no way to extend the zoom range beyond 24-
120, because these adapters were really HUGE.
But otherwise, in its 24-120 range the R1 is optically better than most
DSRLs in its price range. You would have had to buy a very expensive
lens to outperform the R1 optically.
Sony didn't follow up on the R1 because there was more money to be made
by selling lenses to folks who bought DLSR. To make an example, the
CZ16-80 lens I bought for the A350 cost more than the body of the A350,
and so is the case of the 70-300 G SSM (unfortunately also that lens is
necessary if you are using the A350, because anything else is optically
not capable to support the resolution of the A350).
David J Taylor
> In article <pm2Rk.84289$E41....@text.news.virginmedia.com>, David J
> Taylor says...
>
>> How much lag do you see in low-light, with the shutter speed set to,
>> for example, 1/1000s?
>
> In that case you see no shutter lag (well, I can speak for the Olympus
> 8080 and Sony R1).
Perhaps you're lucky. I've just tried all the compact cameras in the
house, and they /all/ show blurring when they are rotated in a dark
environment - as if you were panning. Most of them, with the exception of
the Nikon 8400, also show a very perceptible lag between what's happening
in from of the lens, and what is shown in the LCD. Just wave your hand in
front of the camera to see this happening. In some of the cameras, the
lag was even perceptible with the scene in broad sunlight.
Cheers,
David
David J Taylor
> In article <Vp2Rk.84291$E41....@text.news.virginmedia.com>, David J
> Taylor says...
>
>> They did - Sony made the R1 but it ended up having less zoom range,
>> and being a brute of a camera becuase of the size of the sensor.
>> Did it sell?
>
> I bought it and can tell you that it's a fine camera. The only problem
> is that the sensor Sony chose was not that good at high ISO and that
> for practical purposes there was no way to extend the zoom range
> beyond 24- 120, because these adapters were really HUGE.
It's a pity, because it was a camera I was really looking forward to. The
size and weight put me off. I suppose its zoom must be similar to the
16-85mm VR lens I have now (no IS/VR on the Sony, of course), and I do
find that a good range. It's nice to be able to quickly swap to the
70-300mm VR (105-450mm 35mm equivalent FoV) for those distant shots,
though. That's an 18.75:1 zoom range.
Have you compared the A350/R1/8080 taking the same scene?
Cheers,
David
Alfred Molon
Taylor says...
> Perhaps you're lucky. I've just tried all the compact cameras in the
> house, and they /all/ show blurring when they are rotated in a dark
> environment - as if you were panning.
Have you tried setting them to a short exposure time, for instance
1/100s? It would seem that the motion blur emulation was activated with
your cameras.
Alfred Molon
Taylor says...
> It's a pity, because it was a camera I was really looking forward to. The
> size and weight put me off. I suppose its zoom must be similar to the
> 16-85mm VR lens I have now (no IS/VR on the Sony, of course), and I do
> find that a good range.
It's quite likely that the lens of the R1 is better than the Nikon 16-
85. Almost sure for what concerns vignetting and quite likely for what
concerns resolution.
> It's nice to be able to quickly swap to the
> 70-300mm VR (105-450mm 35mm equivalent FoV) for those distant shots,
> though. That's an 18.75:1 zoom range.
I hate swapping the lens, because dust could come into the body. It's a
bit tough holding the body down so that dust (hopefully) won't come in
and at the same time holding two lenses with the mount side down,
quickly so that dust won't come onto the lens lid etc. Some places are
quite dusty. Over 99% of the time I use the CZ16-80.
> Have you compared the A350/R1/8080 taking the same scene?
These cameras have all different resolutions, so you can't directly
compare the lenses. But the CZ16-80 has some ugly, non-correctable
vignetting when you use it with a polariser filter (and I bought a slim
one). Which means that a number of images have to be edited manually
with the copy tool (overwrite the blackened sky corners with parts of
sky which have a normal brightness).
The 8080 had no such problems and the images of the R1 could all be
corrected during the RAW conversion, but the vignetting of the CZ16-80
is simply too strong.
David J Taylor
> In article <pceRk.84476$E41....@text.news.virginmedia.com>, David J
> Taylor says...
>
>> Perhaps you're lucky. I've just tried all the compact cameras in the
>> house, and they /all/ show blurring when they are rotated in a dark
>> environment - as if you were panning.
>
> Have you tried setting them to a short exposure time, for instance
> 1/100s? It would seem that the motion blur emulation was activated
> with your cameras.
I tried that by setting the flash to "on", and it made no difference on
most cameras. With the Panasonic FZ20, setting the exposure to 1/1000s
resulted in the display being invisible in dark conditions, with the Nikon
8400 the lag and blurring were unchanged at 1/3000s exposure. In the very
low light, the sensor needs a longer exposure to create a sufficiently
acceptable image for display.
Of more concern, to be honest, was the visible delay between the subject
movement and the movement portrayed on the LCD display. This was
noticeable even in bright lighting conditions on some of the cameras.
Cheers,
David
clayton J
You've never heard of filter step-up rings that allow you to use larger filters
on your cameras? They cost about $4-5 from reputable dealers. I always buy
oversized filters so I may use the same ones on all my cameras. I have to travel
light and for great distances with minimal equipment and still provide for the
most adaptable "anything can happen" configurations. I use the step-up rings on
the cameras with smaller filter-thread diameters. No vignetting ever, no matter
how many that you need to stack.
You people seriously need some remedial photography classes ... or something.
David J Taylor
> In article <lheRk.84480$E41....@text.news.virginmedia.com>, David J
> Taylor says...
[]
> 85. Almost sure for what concerns vignetting and quite likely for what
> concerns resolution.
Those who are interested can probably check the review Web sites.
> I hate swapping the lens, because dust could come into the body. It's
> a bit tough holding the body down so that dust (hopefully) won't come
> in and at the same time holding two lenses with the mount side down,
> quickly so that dust won't come onto the lens lid etc. Some places are
> quite dusty. Over 99% of the time I use the CZ16-80.
Yes, dust can be an issue, although I tend not to travel to dusty places.
My current DSLR has built-in sensor cleaning, so that may help, but even
with my previous DSLR dust wasn't that much of an issue. I did adopt a
regime of a nightly sensor clean, just with a blower.
>> Have you compared the A350/R1/8080 taking the same scene?
>
> These cameras have all different resolutions, so you can't directly
> compare the lenses. But the CZ16-80 has some ugly, non-correctable
> vignetting when you use it with a polariser filter (and I bought a
> slim one). Which means that a number of images have to be edited
> manually with the copy tool (overwrite the blackened sky corners with
> parts of sky which have a normal brightness).
> The 8080 had no such problems and the images of the R1 could all be
> corrected during the RAW conversion, but the vignetting of the CZ16-80
> is simply too strong.
I appreciate that the resolution may differ, but I am thinking about the
same scene displayed at the same size, whether on a print, TV or computer
monitor. I seem to be spared significant vignetting problems with the
Nikon 16-85mm + 2nd-line polarising filter.
Cheers,
David
Don Stauffer
Yes indeed. That lens does not need to move, since it does not block
the film/image chip area. The TLR preceded the SLR. The SLR mfgs had
to come up with a reliable way to have the mirror flip up, and then
return exactly to the same place it left (staying in alignment). And,
at a price people could afford.
J. Clarke
A side by side between the G10 and the 50D would be interesting IMO.
Both approximately 15 megapixels, same generation of technology, same
manufacturer.
--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Paul Furman
Ah, that's what those are all about, thanks. Presumably they could use
cheaper optics in the viewfinder lens, or is it simply a duplicate lens?
--
Paul Furman
www.edgehill.net
www.baynatives.com
all google groups messages filtered due to spam
Alfred Molon
says...
> You've never heard of filter step-up rings that allow you to use larger filters
> on your cameras? They cost about $4-5 from reputable dealers. I always buy
> oversized filters so I may use the same ones on all my cameras. I have to travel
> light and for great distances with minimal equipment and still provide for the
> most adaptable "anything can happen" configurations. I use the step-up rings on
> the cameras with smaller filter-thread diameters. No vignetting ever, no matter
> how many that you need to stack.
>
> You people seriously need some remedial photography classes ... or something.
Sure, but I have already spent 100+ Euro on this high quality slim line
polariser filter. And no, Sony didn't tell me that I had to use an
oversized filter with a step-up ring. They never mentioned anywhere, so
how was I supposed to know that you need an oversized polariser filter?
All cameras I've been using previously didn't have this vignetting
problem.
gerald-bante
>Sure, but I have already spent 100+ Euro on this high quality slim line
>polariser filter. And no, Sony didn't tell me that I had to use an
>oversized filter with a step-up ring. They never mentioned anywhere, so
>how was I supposed to know that you need an oversized polariser filter?
>All cameras I've been using previously didn't have this vignetting
>problem.
I suggest you test that expensive filter for strength and homogeneity. I test
all of them that come my way by a simple test against some lab-grade polarizer.
Turned 90 degrees and held up to a bright and even light you can quickly tell if
it's worth the money. Some famous brands that I have bought for over $80 fared
less well than $14 generic polarizers. Until you test them you may have gotten
ripped off.
You *never* get what you pay for any more.
dj_nme
Keep in mind that TLR cameras almost exclusively use medium format
roll-film.
The really cheap end of the TLR camera market (EG: Kodak Duaflex) have a
fixed non-focusing lens and a reflex viewfinder, sort of a "pretend" TLR
camera.
The serious-amateur/low-end-pro TLR cameras with a fixed lens (EG:
Yashica Mat) tend to have a slightly faster viewfinder lens (EG: f1:3.2
lens/f1:2.8 viewfinder) to exaggerate out of focus blur and make
focusing easier.
The top end of the market have interchangeable lenses and viewfinders,
some even have accessory eye-level pentaprism finders and co-existed in
the studio with medium-format SLR camera up until digital killed off
most pro use of film.
Chris Malcolm
> In article <Vp2Rk.84291$E41....@text.news.virginmedia.com>, David J
> Taylor says...
>> They did - Sony made the R1 but it ended up having less zoom range, and
>> being a brute of a camera becuase of the size of the sensor. Did it sell?
> I bought it and can tell you that it's a fine camera. The only problem
> is that the sensor Sony chose was not that good at high ISO and that for
> practical purposes there was no way to extend the zoom range beyond 24-
> 120, because these adapters were really HUGE.
The wide angle adapter was wide and flat, and could easily be carried
in a coat pocket. And if you carried the R1 with its lens extension
cradle attached you could add and subtract the wide angle in half the
time you could change the lens on a DSLR. What's more its optical
performance was very good indeed.
Using the R1 in that way was so quick and convenient that I often
carried it about with cradle on and wide angle in my pocket.
You're right about the truly enormous tele extension, however.
> But otherwise, in its 24-120 range the R1 is optically better than most
> DSRLs in its price range. You would have had to buy a very expensive
> lens to outperform the R1 optically.
That was true even with the wide angle extension on it.
--
Chris Malcolm
Chris Malcolm
I've repeated a few of my best R1 shots with an A350 plus SAL18-250mm
zoom. There's a slight loss of contrast but the extra detail you'd
expect from the 14MP is there. At first I thought the loss of contrast
was a natural consequence of the larger number of lenses in the more
complex longer zoom, but now that I've noticed the very much wider
dynamic range in the A350 images, it may be a consequence of that. I'd
say that generally speaking when compared at pixel level and when both
lenses are used at their best apertures the SAL18-250 is the effective
equal in performance of the R1's zoom when used in the same zoom range
on a 14MP sensor, and up to the extra resolution.
At its wide and long extremes the optical performance falls off a bit,
I'd guess down to about 7MP standards, since downsizing to 7MP
conceals the optical flaws.
Two improvements of the A350 over the R1 which are very obvious as you
just wander about snapping things is that the exposure is much more
accurate. Highlights are very much more rarely blown. The second is
that not only is the autofocus much faster, and operates well in worse
conditions, but it's also more often right on the nail.
--
Chris Malcolm
Chris Malcolm
> In article <f06bh4tsdh79j9rs5...@4ax.com>, clayton J
> says...
>> You've never heard of filter step-up rings that allow you to use larger filters
>> on your cameras? They cost about $4-5 from reputable dealers. I always buy
>> oversized filters so I may use the same ones on all my cameras. I have to travel
>> light and for great distances with minimal equipment and still provide for the
>> most adaptable "anything can happen" configurations. I use the step-up rings on
>> the cameras with smaller filter-thread diameters. No vignetting ever, no matter
>> how many that you need to stack.
>>
>> You people seriously need some remedial photography classes ... or something.
> Sure, but I have already spent 100+ Euro on this high quality slim line
> polariser filter. And no, Sony didn't tell me that I had to use an
> oversized filter with a step-up ring. They never mentioned anywhere, so
> how was I supposed to know that you need an oversized polariser filter?
> All cameras I've been using previously didn't have this vignetting
> problem.
It's not a camera problem, it's a wide lens problem. If you want a
wide lens to operate without vignetting with standard sized filters
you have to make the lens body wide enough to take the width of filter
required. Or you can slim it down and require the use of slim filters
or step-out rings. Since polarisers don't work well with wide lenses
anyway, because they're so wide the polarisation shifts a lot over the
image, wide lenses will very often not accommodate the extra depth of a
polariser, even a slimline one.
--
Chris Malcolm
David J Taylor
> David J Taylor
[]
>> Have you compared the A350/R1/8080 taking the same scene?
>
> I've repeated a few of my best R1 shots with an A350 plus SAL18-250mm
> zoom. There's a slight loss of contrast but the extra detail you'd
> expect from the 14MP is there. At first I thought the loss of contrast
> was a natural consequence of the larger number of lenses in the more
> complex longer zoom, but now that I've noticed the very much wider
> dynamic range in the A350 images, it may be a consequence of that. I'd
> say that generally speaking when compared at pixel level and when both
> lenses are used at their best apertures the SAL18-250 is the effective
> equal in performance of the R1's zoom when used in the same zoom range
> on a 14MP sensor, and up to the extra resolution.
>
> At its wide and long extremes the optical performance falls off a bit,
> I'd guess down to about 7MP standards, since downsizing to 7MP
> conceals the optical flaws.
>
> Two improvements of the A350 over the R1 which are very obvious as you
> just wander about snapping things is that the exposure is much more
> accurate. Highlights are very much more rarely blown. The second is
> that not only is the autofocus much faster, and operates well in worse
> conditions, but it's also more often right on the nail.
Thanks for that, Chris. About what you'd expect considering that the A350
and R1 have similar-sized sensors. Would the focus difference be due to
phase-detection (A350) versus maximum-contrast (R1)? The exposure
metering should be as though, shouldn't it? Or is it that the separate
focus on the A350 can offer a greater dynamic measurement range than the
on-sensor exposure metering of the R1?
SAL - you have me puzzled!
Cheers,
David
Alfred Molon
> Thanks for that, Chris. About what you'd expect considering that the A350
> and R1 have similar-sized sensors. Would the focus difference be due to
> phase-detection (A350) versus maximum-contrast (R1)? The exposure
> metering should be as though, shouldn't it?
Well, I have noticed that the A350 meters much more conservatively than
the R1, sometimes even resulting in underexposed images. The R1 instead,
probably due to its high ISO/shadow noise weakness, exposes a bit more
aggressively and allows perhaps a % or two of the image to be
overexposed.
> Or is it that the separate
> focus on the A350 can offer a greater dynamic measurement range than the
> on-sensor exposure metering of the R1?
All phase AFs are faster than contrast AFs.
Alfred Molon
> I'd
> say that generally speaking when compared at pixel level and when both
> lenses are used at their best apertures the SAL18-250 is the effective
> equal in performance of the R1's zoom when used in the same zoom range
> on a 14MP sensor, and up to the extra resolution.
Well, you might not always be able to shoot at F8. The CZ16-80 is sharp
from F5 onwards, while I doubt that the SAL18-250 is that sharp at such
apertures.
BTW, how good is the SAL18-250 beyond 100mm?
Alfred Molon
> It's not a camera problem, it's a wide lens problem. If you want a
> wide lens to operate without vignetting with standard sized filters
> you have to make the lens body wide enough to take the width of filter
> required. Or you can slim it down and require the use of slim filters
> or step-out rings. Since polarisers don't work well with wide lenses
> anyway, because they're so wide the polarisation shifts a lot over the
> image, wide lenses will very often not accommodate the extra depth of a
> polariser, even a slimline one.
Sure, but if you buy an A350 and care about image quality (resolution)
there are not many options out there. You'll want to buy a CZ16-80. The
only other zoom lens in this focal length range which comes close is the
Tamron 17-50, probably with less vignetting due to its wider filter
thread, but with a substantially reduced focal length range. It's a PITA
changing lenses.
David J Taylor
[]
> All phase AFs are faster than contrast AFs.
Yes, I appreciate that, Alfred, thanks for your confirmation.
My last should have read:
"The exposure metering should be as good though (on the R1 as the A350),
shouldn't it? Or is it that the separate meter sensor on the A350 can
offer a greater dynamic measurement range than the on-sensor exposure
metering of the R1?"
I would still be interested in a comparison between the image quality on
the Sony A350, Sony R1, and Olympus 8080 cameras which I believe you have
owned.
David
Alfred Molon
Taylor says...
> I would still be interested in a comparison between the image quality on
> the Sony A350, Sony R1, and Olympus 8080 cameras which I believe you have
> owned.
I still have them all, but how to do this comparison? What scene should
I shoot? An outdoor scene with everything in focus?
David J Taylor
> In article <go0Sk.85648$E41....@text.news.virginmedia.com>, David J
> Taylor says...
>
>> I would still be interested in a comparison between the image
>> quality on the Sony A350, Sony R1, and Olympus 8080 cameras which I
>> believe you have owned.
>
> I still have them all, but how to do this comparison? What scene
> should I shoot? An outdoor scene with everything in focus?
Alfred,
I have an indoor test scene which I usually use with new cameras as a
basic function/quality check.
But I was hoping for some more like: "If I print at A4 size, I can't tell
the difference" or "The larger sensor usually provides a better quality
image", or whatever.
I can say: The image quality from my DSLR is significantly better that
those from my compact camera, but as my compact camera was chosen for a
large zoom range in a very compact package, that doesn't surprise me." To
me, the difference is obvious, but the compact is much smaller than the
8080.
David
Chris Malcolm
>> Alfred Molon wrote:
>>> says...
>>>> "Roger N. Clark (change username to rnclark)" <user...@qwest.net>
>>>> wrote:
>>>>> Why do DSLR's still use mirrors?
>>>
>>> Most people probably don't know this fine distinction and would
>>> consider any camera with a large sensor and interchangeable lenses a
>>> DSLR.
>>
>> This is true, even though it still has some of disadvantages of a P&S,
>> it at least has the larger sensor. Though if someone could make a ZLR
>> with a larger sensor, and a wide zoom range, it'd be better than the
>> G1.
> They did - Sony made the R1 but it ended up having less zoom range, and
> being a brute of a camera becuase of the size of the sensor. Did it sell?
I think the main reason it didn't sell well is that it fell between
two large stools of marketing and public perception. Most people
couldn't the point of a non-DSLR which was as big and heavy as a
DSLR. But if all you wanted was a DSLR with a good general purpose
zoom, it was exceptionally good image quality value for money.
--
Chris Malcolm
Chris Malcolm
> David J Taylor wrote:
>> They did - Sony made the R1 but it ended up having less zoom range, and
>> being a brute of a camera becuase of the size of the sensor. Did it sell?
> It runs into the same problems as all of these ZLRs. By the time you put
> on the long lens, and in the case of the R1 the larger sensor, you're
> just not saving much in manufacturing cost versus using a lens mount and
> a mirror, plus you still have all the other disadvantages of the P&S to
> contend with. You've saved no weight and no size, and very little money,
> and you end up with decidedly inferior results compared to a D-SLR.
Sony claimed that being able to have the lens much closer to the
sensor enabled them (i.e. Zeiss) to produce a high quality zoom much
more cheaply. Some reviewers suggested so much more cheaply that to
match its quality in a DSLR zoom you'd have to pay more than the cost
of the entire R1 just for the lens.
--
Chris Malcolm
Chris Malcolm
> In article <6nqi0l...@mid.individual.net>, Chris Malcolm says...
>> It's not a camera problem, it's a wide lens problem. If you want a
>> wide lens to operate without vignetting with standard sized filters
>> you have to make the lens body wide enough to take the width of filter
>> required. Or you can slim it down and require the use of slim filters
>> or step-out rings. Since polarisers don't work well with wide lenses
>> anyway, because they're so wide the polarisation shifts a lot over the
>> image, wide lenses will very often not accommodate the extra depth of a
>> polariser, even a slimline one.
> Sure, but if you buy an A350 and care about image quality (resolution)
> there are not many options out there. You'll want to buy a CZ16-80. The
> only other zoom lens in this focal length range which comes close is the
> Tamron 17-50, probably with less vignetting due to its wider filter
> thread, but with a substantially reduced focal length range. It's a PITA
> changing lenses.
Aren't you like me moving up to the Sony A350 from an R1? The CZ16-80
does sound like a remarkably good lens. I do a lot of architectural
photography, and found that the R1's 14.3mm wasn't quite enough, and
with the wide angle extension which brought it to 11.5mm, was just a
touch short of that extremely useful 90 degree field of view. So the
CZ16-80 wasn't wide enough for me.
I don't know how high your quality standards are, but mine were to
begin with lenses which at their best had as good performance as the
R1. i.e. when downsized to the R1's 10MP. The two zooms I have which
in practice I find more than fulfil that requirement are the Sigma
10-20mm and the Sony (Tamron) 18-250mm. Not as good as the R1 at 10mm
and 250mm, but IMHO as good over a larger zoom range than the R1 could
get even with its extension lenses, and at their best with the extra
detail resolution you'd expect from the 40% extra image pixels.
--
Chris Malcolm
Chris Malcolm
That's what they say :-) It's *much* faster, works better in the dim
light of overcast days, and in casual fast opportunistic snapping
catches the exact sharp perfect focus more often.
> The exposure
> metering should be as though, shouldn't it? Or is it that the separate
> focus on the A350 can offer a greater dynamic measurement range than the
> on-sensor exposure metering of the R1?
The A350 meters exposure in two different ways. When using the optical
viewfinder it does the same as other DSLRs (whatever that is). When
using the separate live view sensor (smaller than the image sensor) it
used that entire LV sensor to do the exposure, and as a result catches
the tiniest highlights with very accurate exposure.
I use Picasa to organise my images and do minor snapshot type
editing. I always push the "fix exposure" button just to see what
happens. With the R1's images it nearly always made at least a slight
adjustment. With the A350 it rarely does anything. I note that I don't
have to underexpose on the A350 to avoid losing the occasional
highlight, and it has enough dynamic range in RAW that that kind of
conservative highlight exposure doesn't lose any shadow detail
compared to the R1, quite the reverse.
> SAL - you have me puzzled!
SAL18-250mm is Sony's name for their rebadged and slightly modded
version of the Tamron 18-250mm.
--
Chris Malcolm
Chris Malcolm
>> In article <go0Sk.85648$E41....@text.news.virginmedia.com>, David J
>> Taylor says...
>>
>>> I would still be interested in a comparison between the image
>>> quality on the Sony A350, Sony R1, and Olympus 8080 cameras which I
>>> believe you have owned.
>>
>> I still have them all, but how to do this comparison? What scene
>> should I shoot? An outdoor scene with everything in focus?
> Alfred,
> I have an indoor test scene which I usually use with new cameras as a
> basic function/quality check.
> But I was hoping for some more like: "If I print at A4 size, I can't tell
> the difference" or "The larger sensor usually provides a better quality
> image", or whatever.
I certainly couldn't tell the difference in detail between the R1 and
the A350 at A4. Probably a close look at an A2 print would be
required. More detail in the A350, less contrast (easily fixed in an
editor), much wider dynamic range, much less noise at higher ISOs, and
more latitude in all directions from the RAW image.
The R1's images usually look better in a straight ex-camera jpeg, more
vivid punch. The A350's images have about as much more detail as you'd
expect, and more detail can be brought out of the highlights and deep
shadows.
--
Chris Malcolm
David J Taylor
> David J Taylor
>> The exposure
>> metering should be as good though, shouldn't it? Or is it that the
>> separate meter sensors on the A350 can offer a greater dynamic
>> range than the on-sensor exposure metering of the R1?
>
> The A350 meters exposure in two different ways. When using the optical
> viewfinder it does the same as other DSLRs (whatever that is). When
> using the separate live view sensor (smaller than the image sensor) it
> used that entire LV sensor to do the exposure, and as a result catches
> the tiniest highlights with very accurate exposure.
Do you notice any significant difference between exposure measured in the
standard and live-view modes?
> I use Picasa to organise my images and do minor snapshot type
> editing. I always push the "fix exposure" button just to see what
> happens. With the R1's images it nearly always made at least a slight
> adjustment. With the A350 it rarely does anything. I note that I don't
> have to underexpose on the A350 to avoid losing the occasional
> highlight, and it has enough dynamic range in RAW that that kind of
> conservative highlight exposure doesn't lose any shadow detail
> compared to the R1, quite the reverse.
I do find that I get the results I prefer with the Nikon D40 and D60 set
to -1/3 stop exposure compensation, but that might just be the way I
meter.
>> SAL - you have me puzzled!
>
> SAL18-250mm is Sony's name for their rebadged and slightly modded
> version of the Tamron 18-250mm.
Thanks, I saw your later post on this as well.
David
Alfred Molon
> Aren't you like me moving up to the Sony A350 from an R1?
Yep.
> The CZ16-80
> does sound like a remarkably good lens. I do a lot of architectural
> photography, and found that the R1's 14.3mm wasn't quite enough, and
> with the wide angle extension which brought it to 11.5mm, was just a
> touch short of that extremely useful 90 degree field of view. So the
> CZ16-80 wasn't wide enough for me.
Well, I do a lot of panorama stitching so wideness of a lens is a non-
issue, as I can go down to whatever angle of view by stitching
individual images together. Has the advantage that all geometric
distortions are automatically corrected.
Alfred Molon
Taylor says...
> But I was hoping for some more like: "If I print at A4 size, I can't tell
> the difference" or "The larger sensor usually provides a better quality
> image", or whatever.
Since the indoor image would be taken on a tripod at lowest ISO, the
larger sensor wouldn't give (almost) any noise advantage, only more
resolution.
DRS
news:gf4b9...@news7.newsguy.com
> David J Taylor wrote:
[...]
>> I appreciate that the resolution may differ, but I am thinking about
>> the same scene displayed at the same size, whether on a print, TV or
>> computer monitor. I seem to be spared significant vignetting
>> problems with the Nikon 16-85mm + 2nd-line polarising filter.
>
> A side by side between the G10 and the 50D would be interesting IMO.
> Both approximately 15 megapixels, same generation of technology, same
> manufacturer.
What precisely are you looking for? I have a 50D with 28-80L and 100-300L
lenses, and my partner has a G10.