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Old Apr 27, 2006, 1:49 PM   #1
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I recently purchased a Canon EOS 20D camera which has a RAW format option. In low light conditions, is it feasible to take a picture without a tripod in a RAW format and reexpose the picture when editing in a RAW format? Can I also play with the white balance while editing? Are there noise issues?
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Old Apr 27, 2006, 2:05 PM   #2
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RAW will allow you to underexpose a little and then correct but I doubt it would help. Using a high ISO will help but that's where noise may intrude. It's always best to get the shot with some noise than miss the shot because you didn't increase the ISO.

I do wonder what it is you are shooting that you want to avoid a tripod. By using a fast shutter speed you may miss the effect you are looking for.

You can change the white balance during RAW processing.

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Old Apr 28, 2006, 11:43 AM   #3
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The better exposed the photo is to begin with, the better off you'll be.

Although you do have some leeway in post processing, it's not as much as some people think without image degradation if the exposure isn't correct (and you can lose some Dynamic Range deliberately underexposing).

As for noise, if you deliberatelly underexpose to get faster shutter speeds and brighten later during Post Processing, you'll get more noise, just as if you used a higher ISO speed.

As a general rule, you're better off increasing ISO speed if needed for shutter speed purposes versus trying to underexpose, unless you "run out of ISO speed".

I've been known to deliberately underexpose after reaching a camera's highest available ISO speed (because sometimes bad noise is preferrable to bad motion blur). But, don't expect pretty results if you do that.

Of course, as Nagasaki hinted, keeping ISO speeds set lower and using a tripod is your best bet for non-stationary subjects in low light.

Your 20D is relatively clean at higher ISO speeds if they're needed, depending on the print and viewing sizes needed and how even the lighting is.

A brighter lens can go a long ways, too (so that you don't need to set ISO speeds as high for the desired results).

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Old Apr 28, 2006, 12:01 PM   #4
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Thanks all for the advice. Trying to get a few ideas here.

The other nite I was at a school function for my son. I was seated about 35 feet from the stage that he was on. I tried taking pictures of him on the stage in a RAW format using 200 ISO with 1/30 exposure with no light using image stabilization. Most of the pictures had a high noise factor. The pictures also were not sharp. It was unfeasible to use a tripod given it was in an auditorium that seats about 300 people. I had tried to do a similar type of shooting in a shopping mall about 2 weeks earlier as an experiment and had better results. My wife and I are planning a vacation during the summer and if we ended up in a city, it would be nice to do some outside nite photography in a RAW format without a tripod if possible. Not sure if we are doing Paris or Rome and Venice.
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Old Apr 28, 2006, 12:22 PM   #5
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If you had high noise at ISO 200, it sounds like you underexposed signficantly.

What lens were you using?

For indoor existing light shooting of non-stationary subjects you'll usually want something f/2.8 or brighter (you'll need to go with a prime versus zoom to get brighter than f/2.8 ), and you'll *still* need higher ISO speeds in most indoor conditions.

If you plan on doing a lot of low light shooting, invest in some bright primes and/or f/2.8 zooms.

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Old Apr 28, 2006, 4:32 PM   #6
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Runny- punch that ISO up to 800 and get a faster shutter going for you. I use all IS lenses and they do help, but you have to contend with subject movement too.
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Old Apr 29, 2006, 3:47 AM   #7
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With the KM 7D + Sigma 20mm/1.8 I never need a tripod even if light is not enough for reading. The combination of image stabilisation + high iso + fast lense + wide angle makes this possible. If light is sufficiently low, the AF hunts up and down and one has to use MF, but for most night shots AF still works. The very shallow DOF is the primary problem. Thus if you have many objects with different distance in the picture most of them will not be sharp.
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Old Apr 29, 2006, 7:37 AM   #8
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Setiprime wrote:
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Runny- punch that ISO up to 800 and get a faster shutter going for you. I use all IS lenses and they do help, but you have to contend with subject movement too.
I'd agree with that. ;-)

But, it sounds like something else was going on here (settings causing underexposure).

The last time I tried to use ISO 200 at a school function (dance recital), my shutter speeds were running 1/15 second or slower at f/2.8 on a very well lit stage.

So, if the OP was getting 1/30 second at ISO 200, with high noise in the images, my guess is that they were severely underexposed due to a settings issue somewhere, especially if the lens being used didn't have f/2.8 available (and the OP has not said what lens was used).

In that type of lighting, I'd make sure to use a bright zoom or prime, and bump up the ISO speeds to ISO 800or so to keep shutter speeds as fast as possible, making sure I didn't underexpose to keep noise levels manageable.

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