Using EF 24-70mm f/2.8L USM in Low Light

Hello,

This is my first post and I could use some help.

I am a Pro-sumer (Rebel XT), and have been unsatisfied with the EF 24-70mm f/2.8L USM's ability to focus and stay sharp in low light/no flash - (hockey arenas, churches, reception halls, etc.) At 2.8 and ISO 800 and 1600 (shooting AV mode) I can't seem to produce quality pics the same way I do with my EF 70-200mm f/2.8L IS USM or much less expensive EF 50mm f/1.4 USM.

For those of you who have used this lens am I asking too much of it to shoot quality HAND HELD shots as I do with the other two lenses? My understanding was that this lens was very popular for wedding photographers. For the money, I just don't think this lens is performing anywhere close to the other two. I thought it may be a bad copy, but the retailer took some pictures with it and feels it is within spec.

Generally, I shoot a white piece paper to set the custom white balance, select f/2.8, ISO 800-1600 and shoot in AV mode. Anything else I should be doing?

Thanks in advance for your help!

post up a picture please. So others and i can look at it.

The 24-70L is my favorite lens as a wedding photographer, most of the time it sits on my 5D.

Check you shutter speeds, maybe the light is not enough

BugEyes wrote in post #5567090
The 24-70L is my favorite lens as a wedding photographer, most of the time it sits on my 5D.

Check you shutter speeds, maybe the light is not enough

I think it may be just the AF ability of the body the OP is having problems with. 5D with 24-105 at f4 in very dim light still manages to focus.

My 400D had habits of hunting in the same conditions with even faster glass, say 1.8.

elysium wrote in post #5567122
I think it may be just the AF ability of the body the OP is having problems with. 5D with 24-105 at f4 in very dim light still manages to focus.

My 400D had habits of hunting in the same conditions with even faster glass, say 1.8.

I was thinking the same. I have used my 24-70 on both a 5D and 40D and both preformed great in low light, high ISO, AF situations.

your 50mm 1.4 lets in more light. your 70-200 2.8 IS can be used at slower than normal shutter speeds to let in more light.

throw that lens on a xxD or xD camera body and see what it looks like at 800 or 1600 ISO!

Could be the body not focusing well in low light (some are better than others) and the 24-70mm not having IS. But there's no reason the 24-70mm can't take pictures in low light just as good as any other lens (I often shoot in low (or almost NO) light with mine).

I almost guarantee that it's the body. My wife has an XT and I just get frustrated at times with it's ability to lock on AF at times. I know then lenses are good because they work just fine on my 5D.

Try using single-point focus and looking for points in the photo with a sharp edge of contrast.

I use the corner of the eye/tear duct in close shots, the neckline of the shirt in mid shots, etc. You have to know what the camera looks for...

If you are shooting at something with no percievable edges in a dark room, most lenses will hunt. There has to be a detail, texture, or edge to lock focus on.

It is most likely not the lens. I cant see how IS really helps focus in any way, but i guess it is possible. i feel that my lenses focus the same with or without the IS turned on. The IS is effective, just not on focus assist (imo).

get an 430ex flash unit and use the IR assist beam, it works great at close distances.

MikeMcL wrote in post #5568450
It is most likely not the lens. I cant see how IS really helps focus in any way, but i guess it is possible. i feel that my lenses focus the same with or without the IS turned on. The IS is effective, just not on focus assist (imo).

No, IS has no bearing on focus whatsoever. I suggested it merely to explain why the pictures might be softer in low light over a lens that has IS.