Low Light Tips?

I take a lot of family shots at dance recitals, plays etc. Theater lighting has been a great learning experience. I am currently shooting RAW + JPEG. While the JPEGs are sometimes awful colorwise, I can usually post-process the RAW files to an acceptable image.
My question is about focus. Are there any tips about what to do when you are forced by light conditions to shoot wide open? My keeper rate seems low due to the focus being off. User error sometimes, other times maybe just hard conditions for the equipment. I do understand about the shallow depth of field when shooting at f/1.8, and I find the noise levels OK at ISO 1600. I would like to manual focus but I think it would be worse with the low light levels and the challenge of a non-split prism focusing screen.

Can anyone offer advice?

You 85 1.8 should be idea for this and shouldn't really need to see the need for manual focus as it will not help colours etc.

I managed to increase my keeper rate (non flash) up to 70% by simply using the centre AF point for focus as it is generally the sharpest area on the lens. Focus seems to be pretty much dead on.

MF will be possible but with low light/low contrast, it makes it difficult to do so. Are you able to use flash?

elysium-
Flash is not permitted. Color is not a problem, just the shallow depth of field. Getting the correct part of the frame in focus when the subject is constantly moving is my struggle.

Center point focus will help some, but not much you can do with dof if you're shooting wide open. You are at iso 1600 so not much you can do there. You don't say what shutter speeds you are using, are you perhaps able to slow your shutter speed down a bit in order to keep from shooting wide open?

Tim Sheridan wrote in post #5321551
Getting the correct part of the frame in focus when the subject is constantly moving is my struggle.

Are you shooting in AI Servo AF mode? Also what shutter speed are you using - just a thought, maybe its motion blur rather than a focus issue

Use center point AF, one shot if the conditions are really bad.
AiServo if the subject is moving.

Do not focus - recompose. Use an off center AF point instead.

For colors: Set Tungsten WB. AWB sucks in these situations.

Read the performing arts FAQ. Some useful tips there.


Post some images.

For an 85mm at f/1.8 you should be able to get acceptable images/DOF when shooting theater because you should be some distance from the subject. How far away are you when shooting? At 30 feet with the 85mm f/1.8 your DOF should be around two and a half feet deep which should be enough to get someone in focus. At 20 feet the DOF drops to a little over one foot, still enough for someone's head but maybe not for the whole body depending on angles, etc.

What shutter speeds are you using? Are you, or can you, shoot off a tripod or mono pod? Could you be confusing poor focus with motion blur?

Cfn 4 to 1 or 3.

I have used one shot and AI servo focus modes. Dance photos mostly, so lots of movement but not like action sports. Shooting distances of 25-40 ft. I don't think motion blur is the problem as some of the shutter speeds are 1/350-1/500.
Thanks to all who responded, I will try some of the advice offered and will post some examples soon(the images are on my other computer). I think I am probably at the limits of my equipment vs. lighting conditions.

Thanks again for the help!

Tim Sheridan wrote in post #5321551
elysium-
Flash is not permitted. Color is not a problem, just the shallow depth of field. Getting the correct part of the frame in focus when the subject is constantly moving is my struggle.

i had t problem at concerts a lot. then i tried av mode, and chose a focus point in which i was comfortable with. high iso..

i have been dabbling in punk shows, and those are incredibly high energy performers.. so i have been shooting raw only, and burst mode. so like 2 out of 6 would be awesome.. where some would take work to fix, and others were horirible.

that gives me more room for error.

forget jpeg, save the room on your memory card, and shoot raw. it can always be converted to a jpeg anyway.

Here are a couple of the better examples, minimal post, resized for web. Both shot RAW, Manual, Evaluative, AI Servo, no flash.

Picture #1
File name
IMG_0223W.JPG
Shooting Date/Time
3/28/2008 18:49:13
Tv(Shutter Speed)
1/160Sec.
Av(Aperture Value)
F4.0
ISO Speed
1600
Focal Length
85.0 mm

Picture #2 (Motion blur)
File name
IMG_0231W.JPG
Shooting Date/Time
3/28/2008 19:12:31
Tv(Shutter Speed)
1/320Sec.
Av(Aperture Value)
F2.2
ISO Speed
1600
Focal Length
85.0 mm

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This one was shot as jpg, heavy gel lighting.

File name
IMG_0279W.JPG
Shooting Date/Time
3/28/2008 20:02:19
Tv(Shutter Speed)
1/160Sec.
Av(Aperture Value)
F1.8
Metering Modes
Partial metering
ISO Speed
1600
Lens
EF85mm f/1.8 USM

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Last two are OoF. You might want to try One Shot AF...

Shoot with longish (85, 100, 135) primes wide open or close to it and back up so you have more dof. I dont hesitate to bump the ISO way up if I have to, but carefully watch the exposure and shutter speeds to avoid subject blur. Also try to shoot at natural pauses in movement. Careful to meter correctly - spotlight on an actor will really trick averaged metering.

The 85L is my best friend, but I do work from the front row for individual shots.