Front Element Condition
Blinky the Shark
I ran across this demonstration (three images) the other day. It's pretty
good. And succinct.
http://www.lensrentals.com/news/2008.10.30/front-element-scratches
--
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Mark Thomas
> I ran across this demonstration (three images) the other day. It's pretty
> good. And succinct.
>
> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>
>
It would be interesting to see a comparison image from the same lens
undamaged vs damaged, *but shot into the light*.
Alan Browne
One of my hassy lenses has a hard clear plastic lens cap. I've
forgotten to take it off a couple times (though I discover it at some
point before the roll is done...).
When I got the slides and prints, the images appear only slightly soft
at first glance. (And in the small 5x5 proofing prints, you can't tell
at all unless you use a mag glass, it's only at scan time that they show).
After that happened a couple times I took a heavy black marker to it.
(If I'd use the hood more often it would not happen at all... alas).
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Alan Browne
> Alan Browne wrote:
>
>> One of my hassy lenses has a hard clear plastic lens cap. I've
>> forgotten to take it off a couple times (though I discover it at some
>> point before the roll is done...).
>>
>> When I got the slides and prints, the images appear only slightly soft
>> at first glance. (And in the small 5x5 proofing prints, you can't
>> tell at all unless you use a mag glass, it's only at scan time that
>> they show).
>
Go learn to read.
dj_nme
Wouldn't the "acid test" be to see what their reaction would be to a
customer returning a lens in this condition? 8-)
I suspect that if none of the fragments are small enough to fall out and
the cracks are essentially straight through ( | rather than / or \ ) the
thickness of the lens, it should only dim the image slightly.
Not something I'd want to try with my lenses, though. :-o
Gabe McDonnel
wrote:
>
>I ran across this demonstration (three images) the other day. It's pretty
>good. And succinct.
>
>http://www.lensrentals.com/news/2008.10.30/front-element-scratches
In astronomy it's not uncommon to fix a mirror that has a bad scratch or chip by
covering it over or filling it in with flat-black pigment. The images are again
good as new. There is one famous case of a large diameter research telescope
mirror that was shot at a few times with a gun (disgruntled employee, if I
recall), causing huge chinks and conchoidal fractures in it. They filled in the
large holes, painted them black, and the telescope still had most of its
original quality. As long as the lenses' curvatures hold their integrity, you
can get by with quite a bit of defects.
Think of it like putting a chain-link fence-wire up near to your lens and
letting the fuller diameter of the lens shoot around it. Some loss of contrast
due to the illuminated wire but the image itself is still good. If you had a
black magic-marker with you (which I keep in my camera bag) you can blacken that
wire and get a photo as if that wire wasn't even there. (There are some places
where they just won't let you in, or you get shot at if you hopped their fence.
You have to resort to creative methods to get a good photo through some
tight-knit fences. Just a little real-world photography tip from a
pro-photographer, for all those pretend-photographer net-parroting trolls in
this newsgroup. Now they have a new "poly-wanna-cracker" that they can
net-parrot all over the place.)
I have one favorite filter repaired by blackening its defects. It's an antique
filter that was originally designed to enhance flesh-tones. (circa 1950's I
would guess) While on one of my treks I found it in a small photo-shop in a
little Rocky Mountain town. I was originally looking for inexpensive
filter-cells because I needed to build something while on-the-road. When
rummaging through the shop owner's "bargains" box looking for busted filters
that I could disassemble for the parts needed, I spotted one with an unusual
hue. It had a large conchoidal fracture that entered into the filter's surface a
good 2cm. Before committing/destroying this odd filter to my build-it project I
thought I'd test it first to see what it could do--it being such an unusual dark
brownish-orange filter that I've not seen before. For autumn photos it greatly
enhances all the yellows, golds, crimsons, and reds of foliage, as well as
brightening any remaining greens while also deepening blue skies--just what you
want for the right eye-popping balance of fall's contrasting colors. The
camera's auto white-balance compensates for the filter's strong color-shift
while in turn it is boosting the pass-through colors. This is not unlike how a
polarizer will change the original scene's lighting but it can't be duplicated
in editing. The way this filter helps to attenuate and enhance certain
color-bands cannot be duplicated in editing. (I've tried.)
When I found how well it improved fall photos in such a unique way it became
clear that it needed salvaging. I filled in its large fracture with a black
sharpie marker, as well as drawing a black line over another small hairline
crack on another edge. Any contrast robbing problems it had were now gone. It's
a favorite for fall photos and the only color-filter that deserves to be in my
bag for color photos, these days. (Not counting the IR ones.)
Blinky the Shark
> Mark Thomas wrote:
>> Blinky the Shark wrote:
>>> I ran across this demonstration (three images) the other day. It's
>>> pretty
>>> good. And succinct.
>>>
>>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>>>
>>>
>> Yeah, but look how minor the damage was... (gulp)
>>
>> It would be interesting to see a comparison image from the same lens
>> undamaged vs damaged, *but shot into the light*.
>
> One of my hassy lenses has a hard clear plastic lens cap. I've
> forgotten to take it off a couple times (though I discover it at some
> point before the roll is done...).
>
> When I got the slides and prints, the images appear only slightly soft
> at first glance. (And in the small 5x5 proofing prints, you can't tell
> at all unless you use a mag glass, it's only at scan time that they show).
>
> After that happened a couple times I took a heavy black marker to it.
A home-made ND filter! :)
George Kerby
On 11/26/08 5:55 PM, in article
R_2dnVpcz-52fLDU...@supernews.com, "Larry Thong"
<larry...@shitstring.com> wrote:
> Alan Browne wrote:
>
>>>> When I got the slides and prints, the images appear only slightly
>>>> soft at first glance. (And in the small 5x5 proofing prints, you
>>>> can't tell at all unless you use a mag glass, it's only at scan
>>>> time that they show).
>>>
>>> Only proves that you are using cheap crappy glass.
>>
>> Go learn to read.
>
> LOL! Go put me back in your killfile.
>
>
Difficult when you keep nym-shifting, asshole.
sna...@mailinator.com
> Only proves that you are using cheap crappy glass.
Tell me, what would happen if one used expensive crappy glass?
Paul Furman
> I ran across this demonstration (three images) the other day. It's pretty
> good. And succinct.
>
> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
Just a tiny bit of damage for that one ;-)
The only time you will obviously notice front scratches and interior
dust is in a situation like this:
http://edgehill.net/Misc/photography/bokeh/6-28-07/pg1pc5
-where different optical principles apply... note the repeating dust
patterns in each circle, slightly offset.
--
Paul Furman
www.edgehill.net
www.baynatives.com
all google groups messages filtered due to spam
Atheist Chaplain
news:dnrsi49q71bkuagh9...@4ax.com...
then you probably bought Sigma glass ;-)
--
"Calling Atheism a religion is like calling bald a hair color."
Don Hirschberg
Blinky the Shark
> Blinky the Shark wrote:
>> I ran across this demonstration (three images) the other day. It's pretty
>> good. And succinct.
>>
>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>
> Just a tiny bit of damage for that one ;-)
>
> The only time you will obviously notice front scratches and interior
> dust is in a situation like this:
> http://edgehill.net/Misc/photography/bokeh/6-28-07/pg1pc5
> -where different optical principles apply... note the repeating dust
> patterns in each circle, slightly offset.
Good example. And in the one with the leaves in the foreground.
Speaking of bokeh, here's the only test for which I've actually assembled
the results:
http://www.pbase.com/blinkytheshark/image/104408541
PeterZims
wrote:
>Paul Furman wrote:
>
>> Blinky the Shark wrote:
>>> I ran across this demonstration (three images) the other day. It's pretty
>>> good. And succinct.
>>>
>>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>>
>> Just a tiny bit of damage for that one ;-)
>>
>> The only time you will obviously notice front scratches and interior
>> dust is in a situation like this:
>> http://edgehill.net/Misc/photography/bokeh/6-28-07/pg1pc5
>> -where different optical principles apply... note the repeating dust
>> patterns in each circle, slightly offset.
>
>Good example. And in the one with the leaves in the foreground.
>
>Speaking of bokeh, here's the only test for which I've actually assembled
>the results:
>
>http://www.pbase.com/blinkytheshark/image/104408541
Why is the supposedly in-focus LED so soft and blurry in all photos?
Blinky the Shark
Resizing. Compression. The usual. I did not claim that those are "100%
crops".
Here's one from that series. The LED is about 5mm in diameter. But only
a small part of the frame; it's not like I was doing bug shots of just the
LED.
http://blinkynet.net/stuff/led.jpg
Now you can comment on the noise, again ignoring the point of the test,
which was bokeh. Or not, since I already mentioned it.
BlackyMason
wrote:
>PeterZims wrote:
>
>> On Thu, 27 Nov 2008 19:59:23 -0800, Blinky the Shark <no....@box.invalid>
>> wrote:
>>
>>>Paul Furman wrote:
>>>
>>>> Blinky the Shark wrote:
>>>>> I ran across this demonstration (three images) the other day. It's pretty
>>>>> good. And succinct.
>>>>>
>>>>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>>>>
>>>> Just a tiny bit of damage for that one ;-)
>>>>
>>>> The only time you will obviously notice front scratches and interior
>>>> dust is in a situation like this:
>>>> http://edgehill.net/Misc/photography/bokeh/6-28-07/pg1pc5
>>>> -where different optical principles apply... note the repeating dust
>>>> patterns in each circle, slightly offset.
>>>
>>>Good example. And in the one with the leaves in the foreground.
>>>
>>>Speaking of bokeh, here's the only test for which I've actually assembled
>>>the results:
>>>
>>>http://www.pbase.com/blinkytheshark/image/104408541
>>
>> Why is the supposedly in-focus LED so soft and blurry in all photos?
>
>Resizing. Compression. The usual. I did not claim that those are "100%
>crops".
Get a good editor that includes a Lanczos-4 (or better) algorithm for resizings
and rotations (that would be not-PhotoShop for starters, freeware IrfanView
might be better). Then that won't happen. If not, you can touch them up with a
good Fourier transform plugin before hosting them online. It can help to fix all
that muddy mess that bicubic causes. But use it carefully, in the hands of a
novice it can cause nasty ringing artifacts. You might have to apply it in 2-5
stages at slightly lower thresholds then what first seems warranted.
>
>Here's one from that series. The LED is about 5mm in diameter. But only
>a small part of the frame; it's not like I was doing bug shots of just the
>LED.
>
>http://blinkynet.net/stuff/led.jpg
>
>Now you can comment on the noise, again ignoring the point of the test,
>which was bokeh. Or not, since I already mentioned it.
A good 3-5 pixel edge softness on everything too. Pretty poor performance for a
dedicated macro lens. I guess the problem wasn't resizing and compression. If
you have a soft edge to begin with bicubic adds those intermediate (soft-edge)
pixel values into the downsize averaging of subject and background and makes
matters worse. Then again, lots of the problem is due to the very shallow DOF
that's caused by using a large sensor for macro-photography. I see only one bit
that's on the far right that's actually in focus and that too has a 3-4 pixel
softness around it.
Since you insist ... lots of noise on that sensor too. What kind of camera was
it? Were you having to use high ISO because you couldn't use flash for macro on
luminous objects? No, that's not the case, you clearly used flash in that image.
That's why you can't hardly see any light from the red LED. All you're mostly
getting is the reflection from the flash on the cathode platform inside the
plastic LED housing. There's no reason to use high ISO if you're using flash.
Weird.
That can't be a DSLR. No DSLR is ever supposed to be that bad. Everyone in this
newsgroup and forum online says so. Maybe there's something wrong with your fast
phase-contrast auto-focus or something? Or maybe you can't manually focus
properly in low-light conditions through an OVF?
Odd, this again is exactly all the very same problems that that "supposed" P&S
troll keeps talking about. Everything, from software to camera type and lens
problems, completely represented in just one simple photo of an LED. It's a
wonder that nobody takes him seriously.
LOL
Blinky the Shark
> Since you insist ... lots of noise on that sensor too. What kind of camera was
> it?
D60
> Were you having to use high ISO because you couldn't use flash for macro
> on luminous objects?
ISO 400
Blinky the Shark
> BlackyMason wrote:
>
>> Since you insist ... lots of noise on that sensor too. What kind of camera was
>> it?
>
> D60
>
>> Were you having to use high ISO because you couldn't use flash for macro
>> on luminous objects?
>
> ISO 400
Please ignore my last two posts to this thread; I didn't notice I was
responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
useful contributors to the group: sorry about that; it just makes more
noise.
DSLR-idiot-spotlight
wrote:
>BlackyMason wrote:
>
>> Since you insist ... lots of noise on that sensor too. What kind of camera was
>> it?
>
>D60
Oh dear! A $675 DSLR body + dedicated macro lens for $380 (lens alone costing
more than a whole top-shelf P&S camera), for a total of $1,055? A Nikon no less.
And my lowly under $300 P&S cameras can do better than that?
OH MY!!
>
>> Were you having to use high ISO because you couldn't use flash for macro
>> on luminous objects?
>
>ISO 400
And my lowly under $300 P&S cameras can do better than that?
OH MY!!
LOL!!!!!!!!!!!!!!!!!!!!!!
C'mon DSLR trolls, post some more photos. I'm sure I'll find them JUST as
excellent as Blinky's DSLR + dedicated lens performance.
LOL
This just gets better and better. LOL!!!!
Mark Thomas
> Blinky the Shark wrote:
>
>> BlackyMason wrote:
>>
>>> Since you insist ... lots of noise on that sensor too. What kind of camera was
>>> it?
>> D60
>>
>>> Were you having to use high ISO because you couldn't use flash for macro
>>> on luminous objects?
>> ISO 400
>
> Please ignore my last two posts to this thread; I didn't notice I was
> responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
> useful contributors to the group: sorry about that; it just makes more
> noise.
>
>
was going with that one.. (O:
By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
leaving it there?, because I might bookmark it for later use - I
sometimes get asked and that's a nice way to show the concept, and a
good lens example..
Interestingly I've only ever had one Tamron lens where I took any notice
of the bokeh, and that was a 70-150 f3.5 zoom. Not exactly a high end
lens, but geez it was a superb portrait lens, and it really did have
lovely oof effects. I wonder if it was deliberate design or just a
lucky coincidence..
Paul Furman
> Paul Furman wrote:
>
>> Blinky the Shark wrote:
>>> I ran across this demonstration (three images) the other day. It's pretty
>>> good. And succinct.
>>>
>>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>> Just a tiny bit of damage for that one ;-)
>>
>> The only time you will obviously notice front scratches and interior
>> dust is in a situation like this:
>> http://edgehill.net/Misc/photography/bokeh/6-28-07/pg1pc5
>> -where different optical principles apply... note the repeating dust
>> patterns in each circle, slightly offset.
>
> Good example. And in the one with the leaves in the foreground.
>
> Speaking of bokeh, here's the only test for which I've actually assembled
> the results:
>
> http://www.pbase.com/blinkytheshark/image/104408541
Nice soft edges. There is a bit of a bright ring. Supposedly Nikons tend
to have a crisp line and even illumination on the OOF circles, the soft
edge is a clear difference between yours & my examples though taken a
much different focal lengths, distances & lighting contrast. I pretty
much gave up on the bokeh tests though: with a reasonable lens there is
lots of play in the way you set it up & what lighting makes a nice look,
even lenses famous for their soft bokeh can be made to look bad & some
bad lenses can produce nice smooth OOF with care. The slight ring I saw
could be some limited effect for those particular conditions. I would
like to have something that consistently gave a softer edge like those
Tamron samples but the fact is among comparable lenses I can't tell the
difference unless the two sat on the same tripod location.
Speaking of supposedly famous bokeh lenses, mostly I think they are just
nice fast lenses, like 85/1.4 or 135/2 or any macro lens which at close
range produces a lot of OOF in the background. There are bad bokeh
lenses too but it's rare that you can't make those look good. I've got a
Nikon 50mm f/1.2 which is really a pretty bad bokeh lens by it's
reputation... it can be made to look really really freaky bad but
nonetheless it does put out a lot of OOF and with some attention, it's
not hard at all to make beautiful soft buttery bokeh art with it.
Hank Fantor
Let us all bow down and now worship the blurriness of DSLR glass.
LOL
David J Taylor
[]
> Please ignore my last two posts to this thread; I didn't notice I was
> responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
> useful contributors to the group: sorry about that; it just makes more
> noise.
You're forgiven, Blinky! Next it will be claiming that its small-lens
camera can produce identical bokeh....
A useful and interesting series of images - thanks for posting them.
David
Paul Furman
>
> By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
> leaving it there?, because I might bookmark it for later use - I
> sometimes get asked and that's a nice way to show the concept, and a
> good lens example..
>
> Interestingly I've only ever had one Tamron lens where I took any notice
> of the bokeh, and that was a 70-150 f3.5 zoom. Not exactly a high end
> lens, but geez it was a superb portrait lens, and it really did have
> lovely oof effects. I wonder if it was deliberate design or just a
> lucky coincidence..
I have an old 75-150mm f/3.5 Nikon Series E which is probably the same
exact lens. Nikon didn't make them and they were marketed as an bargain
line but it gained a good reputation. Nice compact mf push-pull zoom and
pretty fast specs for the size. It doesn't seem to get super sharp but
has good local contrast.
And also has dust in it:
http://edgehill.net/California/Bay-Area/San-Francisco/gritty/9-4-07-night/full-set/pg3pc12
:-)
not bad with a +2 diopter Canon 300D 2-element closeup lens:
http://edgehill.net/California/Bay-Area/San-Francisco/edgehill-garden/Nursery/plants/9-4-07
JohnCaprial
Actually, it can do even better than that. I was quite surprised that the bokeh
in that f/5.6 image was as minor as it was. When using the proper achromat
close-up lens on a P&S camera at f/2.0, a point of light 20 inches away would
have disappeared beyond the bounds of the image frame. (Not to mention it would
have pixel-sharp edges and details on the in-focus LED.) Note that's even 3
stops wider than you had available in your $380 lens. (What did it cost new when
you bought it, $500? I quoted the year-old prices online today. Nevermind, I
found an original price quoted online, $450. And that's from a discount supplier
known for their low-low prices. LOL.)
Flash wouldn't have been needed at all with my P&S cameras at f/2.0, being able
to even better demonstrate what you hoped to display.
You all really are perfect fools, aren't you.
This is absofuckalutely amazing.
LOL!!
Go ahead, turn tails and praise the soft-edges and blurriness in dedicated DSLR
glass again. I'm getting quite a laugh out of this. LOL Mind if I use your LED
photo as comparison against those P&S SX10 samples? Then we can claim an over
50x's more resolution on the P&S lens compared to dedicated DSLR glass instead
of just 10x's more resolution from the P&S 20x zoom PLUS macro lens. LOL
Mark Thomas
> Mark Thomas wrote:
>>
>> By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
>> leaving it there?, because I might bookmark it for later use - I
>> sometimes get asked and that's a nice way to show the concept, and a
>> good lens example..
>>
>> Interestingly I've only ever had one Tamron lens where I took any
>> notice of the bokeh, and that was a 70-150 f3.5 zoom. Not exactly a
>> high end lens, but geez it was a superb portrait lens, and it really
>> did have lovely oof effects. I wonder if it was deliberate design or
>> just a lucky coincidence..
>
> I have an old 75-150mm f/3.5 Nikon Series E which is probably the same
> exact lens. Nikon didn't make them and they were marketed as an bargain
> line but it gained a good reputation. Nice compact mf push-pull zoom and
> pretty fast specs for the size. It doesn't seem to get super sharp but
> has good local contrast.
>
> And also has dust in it:
> http://edgehill.net/California/Bay-Area/San-Francisco/gritty/9-4-07-night/full-set/pg3pc12
Saw those before - very cool!
> not bad with a +2 diopter Canon 300D 2-element closeup lens:
> http://edgehill.net/California/Bay-Area/San-Francisco/edgehill-garden/Nursery/plants/9-4-07
That's a lovely series. I nearly fell asleep as I was becalmed..
It could well be the same (optically, anyway) lens - mine is a two ring
version, *but* I'm pretty sure both push-pull and twin versions were
available at the time (remember the good old days when there was a good
choice of oem lenses...?) - I liked the feel (and look.. - I'm shallow)
of the two ring version better.
I'm also pretty certain both the Vivitar and Tokina 'equivalent'
competitors were f3.8, so I doubt if they made the 'Nikon'. I think at
the time I knew who made whose budget lenses, but I've long forgotten now.
As an aside, about 4 years after I bought the Tamron, the focus became a
little erratic, and I noticed the scary rattle of a loose internal
element. As I have a little mechanical nouse, I very bravely laid the
lens on a very large white sheet (to catch any flying springs..) and
proceeded to pull it to bits. The element was quite deep inside, but I
eventually got there and managed to successfully put it all back
together. It's currently with a friend, and is still going strong.
*Beautifully* built, unlike another Tamron I had from that era..
Steve
On Thu, 27 Nov 2008 19:59:23 -0800, Blinky the Shark
<no....@box.invalid> wrote:
>Paul Furman wrote:
>
>> Blinky the Shark wrote:
>>> I ran across this demonstration (three images) the other day. It's pretty
>>> good. And succinct.
>>>
>>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>>
>> Just a tiny bit of damage for that one ;-)
>>
>> The only time you will obviously notice front scratches and interior
>> dust is in a situation like this:
>> http://edgehill.net/Misc/photography/bokeh/6-28-07/pg1pc5
>> -where different optical principles apply... note the repeating dust
>> patterns in each circle, slightly offset.
>
>Good example. And in the one with the leaves in the foreground.
>
>Speaking of bokeh, here's the only test for which I've actually assembled
>the results:
>
>http://www.pbase.com/blinkytheshark/image/104408541
That's not such a great test of bokeh for comparing different lenses
because just about any, even those with bad bokeh, will look about the
same using that setup. What you need is something in the background
that has strong highlights, small sources of light, like maybe the sun
glinting off dew on leaves, reflections of a bulb in curved chrome,
whatever. Tough tests like that will really reveal the differences in
bokeh between different lenses.
Steve
jme...@columbus.rr.com
> I ran across this demonstration (three images) the other day. It's pretty
> good. And succinct.
>
> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>
> Blinky
> Killing all posts from Google Groups
> The Usenet Improvement Project:http://improve-usenet.org
> Need a new news feed? http://blinkynet.net/comp/newfeed.html
The damage to the lens had one advantage, it was more or less
symmetrical. That said it just goes to prove what I have long said.
People worry far too much about their lenses. They insist that they
need a UV filter on their lens to "Protect" the lens.
They fear a scratch or chip, no matter how small, will somehow make
their lens un-usable. In reality they seldom show up and while they
can cause some flare or reduced contrast, a little (thin) black felt
tip marker will essentially eliminate that. They are more likely to
loose quality due to that un needed filter than due to the damage
which is not likely to happen anyway.
Stop being a slave to your camera equipment. Equipment is just
tools. Don't worship them, lean to use them. It is not the equipment
that makes a great photograph, it is a great photographer or a poor
one with exceptional luck.
Allen
> On Wed, 26 Nov 2008 15:06:47 -0800, Blinky the Shark <no....@box.invalid>
> wrote:
>
>> I ran across this demonstration (three images) the other day. It's pretty
>> good. And succinct.
>>
>> http://www.lensrentals.com/news/2008.10.30/front-element-scratches
>
> In astronomy it's not uncommon to fix a mirror that has a bad scratch or chip by
> covering it over or filling it in with flat-black pigment. The images are again
> good as new. There is one famous case of a large diameter research telescope
> mirror that was shot at a few times with a gun (disgruntled employee, if I
> recall), causing huge chinks and conchoidal fractures in it. They filled in the
> large holes, painted them black, and the telescope still had most of its
> original quality. As long as the lenses' curvatures hold their integrity, you
> can get by with quite a bit of defects.
>
That was at the MacDonald Observatory in the Davis Mountains in the Big
Bend area of Texas. The biggest problem they have now is not bullet
holes, but smog from Mexican factories. When it was built in 1935 or
thereabouts, the atmosphere out there was crystal clear about 355 days
per year, but, alas, no more. Incidentally, that scope (82 inch
diameter) is no longer their primary instrument but it is still quite
useful.
Allen
Blinky the Shark
> Blinky the Shark wrote:
>> Blinky the Shark wrote:
>>
>>> BlackyMason wrote:
>>>
>>>> Since you insist ... lots of noise on that sensor too. What kind of
>>>> camera was it?
>>> D60
>>>
>>>> Were you having to use high ISO because you couldn't use flash for
>>>> macro on luminous objects?
>>> ISO 400
>>
>> Please ignore my last two posts to this thread; I didn't notice I was
>> responding to the NymshiftingNumbnuts p'n's guy. My bad, and to the
>> useful contributors to the group: sorry about that; it just makes more
>> noise.
>>
>>
> That's ok - if he posts sensibly, why not. But you could see where he
> was going with that one.. (O:
>
> By the way, nice bokeh demo (and nice bokeh!), blinky. Will you be
> leaving it there?, because I might bookmark it for later use - I
> sometimes get asked and that's a nice way to show the concept, and a
> good lens example..
Yes, it'll be there, Mark; I didn't just put it up for this discussion. I
did it for me last summer, then wanted something orderly to share with a
friend, so I made that composite. Just last night I was trying to figure
out what software I used to create that composite, and I'm damned if I
could figure it out. :)
Blinky the Shark
That was a big part of my decision to buy the Tamron. I spent a lot of
time looking at bokeh shots online before getting it (after renting one
for a week). The one I bought, back when the Tamron 90 2.8 was
back-ordered *everywhere*, was the very one I had rented from
LensRentals.com, when it came up for sale a month or two later (they sell
them after x months in the rental inventory).
Blinky the Shark
> Speaking of supposedly famous bokeh lenses, mostly I think they are just
> nice fast lenses, like 85/1.4 or 135/2 or any macro lens which at close
> range produces a lot of OOF in the background. There are bad bokeh
> lenses too but it's rare that you can't make those look good. I've got a
> Nikon 50mm f/1.2 which is really a pretty bad bokeh lens by it's
> reputation... it can be made to look really really freaky bad but
> nonetheless it does put out a lot of OOF and with some attention, it's
> not hard at all to make beautiful soft buttery bokeh art with it.
More bokeh, from my bookmarks:
http://www.pbase.com/miljenko/ccrm_bokeh_tests
And note the composite image for direct comparison.
Blinky the Shark
My pleasure, David. That project started out just for me, and then I
complicated things by putting it together. That's not uncommon, I
suspect. :)
Blinky the Shark
Did I forget to say "this admittedly simple test" in the caption for that
image? Golly, no! It's there, plain as day. :)
Here you go. This didn't include the lens I was considering, though, so I
did my own "admittedly simple" (by golly!) test.
http://www.pbase.com/miljenko/ccrm_bokeh_tests
Steve
On Fri, 28 Nov 2008 13:27:35 -0800, Blinky the Shark
<no....@box.invalid> wrote:
I like that test better except I like to see more than *just* the
point sources of light. True, they do tell you a lot about the
physical properties like the aperture blades, how smooth the light is
inside the highlight, how it bleeds out, etc. But I like the shots of
the kid also.
What I really like to see in the background is some complex shapes,
like the trees and leaves, but that have highlights like sun glinting
on wet leaves, to see how smooth and buttery the highlights play with
the other conplex shapes.
But those are good comparisons.
Steve
Paul Furman
> Paul Furman wrote:
>
>> Speaking of supposedly famous bokeh lenses, mostly I think they are just
>> nice fast lenses, like 85/1.4 or 135/2 or any macro lens which at close
>> range produces a lot of OOF in the background. There are bad bokeh
>> lenses too but it's rare that you can't make those look good. I've got a
>> Nikon 50mm f/1.2 which is really a pretty bad bokeh lens by it's
>> reputation... it can be made to look really really freaky bad but
>> nonetheless it does put out a lot of OOF and with some attention, it's
>> not hard at all to make beautiful soft buttery bokeh art with it.
>
> More bokeh, from my bookmarks:
>
> http://www.pbase.com/miljenko/ccrm_bokeh_tests
>
> And note the composite image for direct comparison.
Those are well done.
Neat look on the 50mm f/1.4 stopped down to f/2.8:
http://www.pbase.com/miljenko/image/37270862
There's all kinds of rounder, softer blobs in the background too.
Blinky the Shark
> Blinky the Shark wrote:
>> Paul Furman wrote:
>>
>>> Speaking of supposedly famous bokeh lenses, mostly I think they are just
>>> nice fast lenses, like 85/1.4 or 135/2 or any macro lens which at close
>>> range produces a lot of OOF in the background. There are bad bokeh
>>> lenses too but it's rare that you can't make those look good. I've got a
>>> Nikon 50mm f/1.2 which is really a pretty bad bokeh lens by it's
>>> reputation... it can be made to look really really freaky bad but
>>> nonetheless it does put out a lot of OOF and with some attention, it's
>>> not hard at all to make beautiful soft buttery bokeh art with it.
>>
>> More bokeh, from my bookmarks:
>>
>> http://www.pbase.com/miljenko/ccrm_bokeh_tests
>>
>> And note the composite image for direct comparison.
>
> Those are well done.
Best page I saw that compared lenses when I was doing my pre-buy homework;
the only one I bookmarked.
> Neat look on the 50mm f/1.4 stopped down to f/2.8:
> http://www.pbase.com/miljenko/image/37270862
> There's all kinds of rounder, softer blobs in the background too.
I don't really care for the iris representations. But that kind of thing
certainly convinced me that I wanted the 9-bladed, rounded blades of the
Tammy.
Blinky the Shark
Yeah, all that on one page - even if separate images with no composite -
would be awesome.
Paul Furman
> Paul Furman wrote:
>
> Best page I saw that compared lenses when I was doing my pre-buy homework;
> the only one I bookmarked.
>
>> Neat look on the 50mm f/1.4 stopped down to f/2.8:
>> http://www.pbase.com/miljenko/image/37270862
>> There's all kinds of rounder, softer blobs in the background too.
>
> I don't really care for the iris representations. But that kind of thing
> certainly convinced me that I wanted the 9-bladed, rounded blades of the
> Tammy.
http://edgehill.net/Misc/photography/2-23-08-tele-athenar/pg2pc8
18 blades :-)
I'm scared too but the polygons can be interesting... some crazy
examples from movies:
http://edgehill.net/Misc/photography/bokeh/movies/pg3pc15
http://edgehill.net/Misc/photography/bokeh/movies/pg4pc21
http://edgehill.net/Misc/photography/bokeh/movies/pg1pc1
Bad bokeh:
http://edgehill.net/Misc/photography/bokeh/movies/pg5
http://edgehill.net/Misc/photography/bokeh/movies/pg1pc2
http://edgehill.net/Misc/photography/bokeh/movies/pg3
Blinky the Shark
> Blinky the Shark wrote:
>> Paul Furman wrote:
>>> Blinky the Shark wrote:
>>
>> Best page I saw that compared lenses when I was doing my pre-buy homework;
>> the only one I bookmarked.
>>
>>> Neat look on the 50mm f/1.4 stopped down to f/2.8:
>>> http://www.pbase.com/miljenko/image/37270862
>>> There's all kinds of rounder, softer blobs in the background too.
>>
>> I don't really care for the iris representations. But that kind of thing
>> certainly convinced me that I wanted the 9-bladed, rounded blades of the
>> Tammy.
>
> http://edgehill.net/Misc/photography/2-23-08-tele-athenar/pg2pc8
> 18 blades :-)
Holy carp! Imagine the 36-point sun stars. :)
> I'm scared too but the polygons can be interesting... some crazy
> examples from movies:
> http://edgehill.net/Misc/photography/bokeh/movies/pg3pc15
Stoplight bokeh.
> http://edgehill.net/Misc/photography/bokeh/movies/pg1pc1
The heck? They look like flowers orsomething. Something's amiss here,
no? Artificial effect of some kind, rather than straigt bokeh?
> Bad bokeh:
> http://edgehill.net/Misc/photography/bokeh/movies/pg5
Ow.
Paul Furman
> Paul Furman wrote:
>
>> Blinky the Shark wrote:
>>> Paul Furman wrote:
>>>> Blinky the Shark wrote:
>>> Best page I saw that compared lenses when I was doing my pre-buy homework;
>>> the only one I bookmarked.
>>>
>>>> Neat look on the 50mm f/1.4 stopped down to f/2.8:
>>>> http://www.pbase.com/miljenko/image/37270862
>>>> There's all kinds of rounder, softer blobs in the background too.
>>> I don't really care for the iris representations. But that kind of thing
>>> certainly convinced me that I wanted the 9-bladed, rounded blades of the
>>> Tammy.
>> http://edgehill.net/Misc/photography/2-23-08-tele-athenar/pg2pc8
>> 18 blades :-)
>
> Holy carp! Imagine the 36-point sun stars. :)
>
>> I'm scared too but the polygons can be interesting... some crazy
>> examples from movies:
>> http://edgehill.net/Misc/photography/bokeh/movies/pg3pc15
>
> Stoplight bokeh.
Radial saw bokeh <g>
>> http://edgehill.net/Misc/photography/bokeh/movies/pg1pc1
>
> The heck? They look like flowers orsomething. Something's amiss here,
> no? Artificial effect of some kind, rather than straigt bokeh?
Maybe they put a scalloped aperture over the front or just keep freaky
bad lenses handy for such effects?
>> Bad bokeh:
>> http://edgehill.net/Misc/photography/bokeh/movies/pg5
>
> Ow.
Conveys the mood though.
Norm Albrams
>
>Maybe they put a scalloped aperture over the front or just keep freaky
>bad lenses handy for such effects?
>
There's a nice editor plugin that can do many such things. Fairly complex to
operate but worth learning. It does some unique things, being able to emulate
the bokeh from any lens imaginable and some that can't be physically made. Use
DOF-map masks for realism. It's a fun toy. I'll let you hunt for it, it's rather
obscure. I already help you with far too much valuable information that none of
you ever deserve to have.