Rebel T1i exposure questons
ransley
section of roof in sun, the section off roof in sun overexposes. Would
the Highlight Priority or Auto Lighting Optimiser help, Would HDR
help. How do I easily set myself up to get even exposures. I am using
factory settings.
sna...@mailinator.com
Buy a graduated filter.
Chris Malcolm
Shoot in RAW to get the extra dynamic range, adjust exposure using
histogram display so that the sunlit roof is just under overexposure,
and then boost the shadow part of the tone curve in
postprocessing. Sounds very complicated if you've never done it
before, but quite quick once you're used to it. You may also be able
to do it by using something like a Dynamic Range Optimiser in your RAW
editor, if it has one of those.
--
Chris Malcolm
John McWilliams
Wait until you have an overcast day, or try early morning, or evening.
Seriously.
John Navas
<879f9304-e9a7-41ef...@l2g2000vba.googlegroups.com>:
HDR is a simple and easy solution.
Take 3-5 shots at a 1 EV interval.
Combine them with HDR software.
--
Best regards,
John (Panasonic DMC-FZ28, and several others)
Hawk
> On Fri, 26 Jun 2009 05:16:48 -0700 (PDT), ransley
> <Mark_R...@Yahoo.com> wrote in
> <879f9304-e9a7-41ef...@l2g2000vba.googlegroups.com>:
>
>> I am trying to take a photo of a house in basicly 50% shade with a
>> section of roof in sun, the section off roof in sun overexposes. Would
>> the Highlight Priority or Auto Lighting Optimiser help, Would HDR
>> help. How do I easily set myself up to get even exposures. I am using
>> factory settings.
>
> HDR is a simple and easy solution.
> Take 3-5 shots at a 1 EV interval.
> Combine them with HDR software.
>
My rule of thumb is either 3 shots 2EV apart, or 5 shots 1EV apart as
the minimum I'd use for the average HDR shot. In some cases where you
are pointed at the sun you may need additional shots to cover the entire
dynamic range.
Newer camera's with 14 bit RAW images may get away with less than the
average 12 bit variety.
(*>
John Navas
wrote in <2tvmpc....@integratelecom.com>:
>John Navas wrote:
>> HDR is a simple and easy solution.
>> Take 3-5 shots at a 1 EV interval.
>> Combine them with HDR software.
>
>My rule of thumb is either 3 shots 2EV apart, or 5 shots 1EV apart as
>the minimum I'd use for the average HDR shot. ...
My own experience is that 1 EV interval is easier to work with and tends
to give better results than 2 EV interval.
Better Solutions
Or use any of the inexpensive CHDK P&S cameras, then any piddly extra
dynamic range from RAW bit-depth becomes meaningless. You wouldn't even
have to use CHDK's 10-bit or 12-bit RAW images either, the 8-bit JPGs would
be plenty of data to work with. CHDK provides a 38EV exposure range for
supported cameras, added to the sensor's 8 to 11 EV dynamic range (46 to 49
EV dynamic range in total). Then there's CHDK's built-in Tv-Av-ISO-Focus
bracketing feature with up to a 4EV step for exposures, for as many
high-speed burst bracketed shots as you want. If bracketing in 1/3EV steps
you could have up to 114 consecutive bracketed images if need be. Who
knows, there could be some scientific application that would require that.
With that much light-level recording range, and precise control over it,
you can properly expose a scene looking out from deep inside a dark cave
where the small cave opening is framing a bright setting sun. The recessed
side cave-walls in deep shadows getting properly exposed while also
managing to properly expose for and record any sunspots seen through the
mouth of that cave too. Or a possible more common occurrence of a similar
scenario (for those decrying "Right, and just where are you going to find a
scene like that?"), inside a dark and deeply curtained room, perhaps a lit
and shrouded candle in a distant corner, with one small glass pane cracked
open to the setting sun, the camera's lens situated of course in the thin
shaft of pale sunlight in a far recess of the large room. What a unique
photo that would make, especially if it captured a solar-eclipse too, not
just ordinary sunspots. Using nothing more than the camera on a tripod. All
caught with just one simple press of the shutter and a bit of
photographer's know-how.
Probably accomplished in 8 (maybe 7) shots of 4EV bracket-steps each. When
including the longer 4EV-step shutter speeds that would be needed of 64s,
8s, and 1s; all the rest at 1/8s, 1/60s, 1/500s, 1/4000s, and 1/32,000s;
will be snapped off in burst mode during about 2 more seconds of image
recording time. With a sensor's 8EV to 11EV dynamic range, a 4EV bracketing
step is more than adequate for exposure overlap. You could probably even
get away with a 6EV bracket step on most any P&S sensor. In that case
though you'd have to write a simple CHDK bracketing script, as the built-in
bracketing feature of CHDK goes no further than 4EV steps shot-to-shot
(selectable in 1/3EV steps for greater control).
John Navas
<answe...@org.org> wrote in
<5a3a45hchdrb4raa1...@4ax.com>:
>On Fri, 26 Jun 2009 17:41:30 +0000 (UTC), Hawk <taoha...@yahoo.com>
>wrote:
>>Newer camera's with 14 bit RAW images may get away with less than the
>>average 12 bit variety.
>Or use any of the inexpensive CHDK P&S cameras, then any piddly extra
>dynamic range from RAW bit-depth becomes meaningless. You wouldn't even
>have to use CHDK's 10-bit or 12-bit RAW images either, the 8-bit JPGs would
>be plenty of data to work with. CHDK provides a 38EV exposure range for
>supported cameras, added to the sensor's 8 to 11 EV dynamic range (46 to 49
>EV dynamic range in total). ...
With all due respect, that hocus pocus.
Better Solutions
wrote:
People should not comment on what they know nothing about.
All CHDK cameras support 64 seconds to 1/33,000 or 1/40,000 second
shutter-speeds. That highest speed is not flash output duration on its
dimmest/fastest setting, which has been measured and documented at
1/64,000th of a second. (Some may possibly go even faster, 1/244,00 second,
but the person finding this on their model of camera didn't document it in
an easily repeatable manner.) That 1/40,000 second is the true fastest
shutter-speed of CHDK cameras. Also documented and recorded by using
high-speed scanning laser beams, the only method that would work. This
isn't counting all the extra ISO ranges and extended aperture ranges too.
Many camera (not all models yet, as it takes some sleuthing for each
firmware version and model number, to find the right addresses to plug into
the routines in CHDK), now support the newly implemented "Extended Range"
shutter-speeds up to 2,048 seconds (34.13 minutes) in shutter-speed "EV
selection" mode. 2,048 seconds to 1/40,000 seconds is a 27.3EV usable
recording range. The other 10.6 EV steps of the 38EV recording range
mentioned previously is provided in ISO and Av ranges. The rest of the 46EV
to 49EV range in the recording range of the sensor itself 38 + 8, 9, 10, or
11.
In CHDK's Tv "factor selection" mode, decimal input mode, then you can go
up to 10,000 seconds, or 166.6 minutes. That would add even more EV range
to those quoted above, but I was trying to be kind and not make everyone
feel even worse about their owning non-CHDK cameras. However, 9 minute (540
second) exposures at low ISOs is about as far as you can make it useful
under normal conditions. Otherwise amp-glow and sensor noise becomes too
much trouble. If your camera is out all night in winter running off of an
insulated battery pack while shooting polar star-trails or tracking views
of the Milky-Way, then exposures much longer than that, maybe even the full
2.77 hour shutter-speed limit, will be possible due to the much colder
ambient temperatures preventing most all sensor noise and amp-glow.
Yes, it might seem like "hocus pocus" to last century's generation, or to
non-CHDK camera owners. But that's what they always say about the science
and technological improvements of the next generation, or about cameras
that are far far better, that they've never owned nor educated themselves
about. Some people call this the blissful ignorance of tunnel-vision. Oh,
how they do love their bliss. Even going so far as to poke their own eyes
out if they can at least remain blissfully ignorant in the dark.
I bet that over-the-air digital HD-TV is just baffling you to no end too,
isn't it. Are you still watching the "How to switch to HD-TV" PSAs on
channels 2, 3, 4, or 5? (They won't be using those for digital channels,
well, maybe Ch.5's slot. Until those frequencies are re-allocated to new
uses it's a safe spectrum to run those PSAs on.)
ransley
> On Fri, 26 Jun 2009 05:16:48 -0700 (PDT), ransley
> <879f9304-e9a7-41ef-b26d-ed8242046...@l2g2000vba.googlegroups.com>:
>
> >I am trying to take a photo of a house in basicly 50% shade with a
> >section of roof in sun, the section off roof in sun overexposes. Would
> >the Highlight Priority or Auto Lighting Optimiser help, Would HDR
> >help. How do I easily set myself up to get even exposures. I am using
> >factory settings.
>
> HDR is a simple and easy solution.
> Take 3-5 shots at a 1 EV interval.
> Combine them with HDR software.
>
> --
> Best regards,
> John (Panasonic DMC-FZ28, and several others)
I think I will try HDR, the sun filtering in different areas and
shadows do make it more difficult
Robert Coe
: ransley <Mark_R...@yahoo.com> wrote:
: > I am trying to take a photo of a house in basicly 50% shade with a
: > section of roof in sun, the section off roof in sun overexposes. Would
: > the Highlight Priority or Auto Lighting Optimiser help,
You won't know until you try them.
: > Would HDR help.
Almost certainly overkill.
: > How do I easily set myself up to get even exposures. I am using
: > factory settings.
Factory settings are for newbies. If you don't want to stay a newbie, you have
to read the manual and try more of the available features.
: Shoot in RAW to get the extra dynamic range, adjust exposure using
: histogram display so that the sunlit roof is just under overexposure,
: and then boost the shadow part of the tone curve in postprocessing.
: Sounds very complicated if you've never done it before, but quite quick
: once you're used to it. You may also be able to do it by using something
: like a Dynamic Range Optimiser in your RAW editor, if it has one of those.
All EOS Canons come with a pretty good RAW editor, Digital Photo Professional.
The latest version has specific settings to boost shadows and/or dim down
highlights. Although it isn't a panacea, it works fairly well. If the camera
didn't come with the latest version of DPP, you can install the version that's
on the CD and download an updater from Canon's Web site.
Bob
Wolfgang Weisselberg
> I am trying to take a photo of a house in basicly 50% shade with a
> section of roof in sun, the section off roof in sun overexposes.
Change your exposure so that the roof doesn't overexpose. If
necessary, use the 'M' mode for that. RAW has more latitude
and can help.
> Would the Highlight Priority or Auto Lighting Optimiser help, Would
> HDR help.
Maybe. Doing HDR right, i.e. that you don't *see* it's a HDR
shot is hard. You do have a sturdy tripod, right?
Waiting for a more overcast day would certainly help.
> How do I easily set myself up to get even exposures. I am using
> factory settings.
By starting to rely less on the camera automatics. Start
reading on basic photography, what exposure times and
aperture settings are and how they relate. Houses don't run
away, you've got time, so play with the 'M' mode for a couple
of hours.
-Wolfgang