IS Effectiveness

I shoot indoor sports (volleyball, basketball) with a 70-200 2.8L w/IS. I've read in a thread that IS is not effective in this situation. I try and keep the shutter speed up above 250 and strive for 500 to 800. To do this I shoot at 2.8 and almost always at 3200 IS0. I personally leave IS on all the time. I figure that it can hurt...or can it?

My questions are;

1. Is IS effective shooting in a gym?

2. What are the negatives of leaving IS on all the time?

IS provides benefit for shake of the camera...e.g. long len held at speeds slower that 1(FL*1.6) for APS-C bodies; or hands rendered more shakey by medical issues or advancing years.

IS provides NO benefit when the SUBJECT is moving and you need to 'freeze' that motion!

The negative of leaving IS on all the time is more rapid consumption of the battery in the camera.

I think this is the very reason you need IS....the only reason I can think someone would say IS isn't good would be the argument that IS doesn't stop motion, only shutter speed does. This is the typical argument between buying f/4 IS lenses vs. f/2.8 without. In your case you already have a f/2.8 lens. Anyway I use the same lens and leave IS on all the time, especially in gymnasiums The only time I turn it off is when using a tripod for fixed objects. I use IS mode two when panning (with or without a tripod).

Wilt wrote in post #4467192
IS provides benefit for shake of the camera...e.g. long len held at speeds slower that 1(FL*1.6) for APS-C bodies; or hands rendered more shakey by medical issues or advancing years.

IS provides NO benefit when the SUBJECT is moving and you need to 'freeze' that motion!

The negative of leaving IS on all the time is more rapid consumption of the battery in the camera.

If battery life is the only negative, then I'm going to leave it on. My battery life is phenominal. I've got two batteries but I've never had to go to the backup.

You mean you can turn the IS off?

On a 30D, one can get bored to death before the battery runs out.

Even for sports, IS can still be useful. But the shutter speeds you're shooting at must be less than a certain threshold. For your 30D, that would be around 1.6 x FL. If you were shooting at much faster than those speeds (such as 1/500-1/800th like you said), the IS would pretty much be useless, as the high shutter speed would nullify the effects of hand shake on image blur.

Thanks, all! It doesn't sound like IS is effective in the indoor sporting events that I shoot most often. It also sounds like the only negative to leaving it on is shortened battery life. Since battery life isn't an issue, I intend to leave IS on.

Anybody see any flaw with this logic?

Not at all, I would just make sure IS is in mod 2 for panning. The camera won't fight you as much when panning that way.

If battery life isn't an issue, keep it on to compensate for camera shake, especialy when you're shooting fully extended. But keep your shutter speed high enough to freeze the action. ... It sounds like you are doing it just right !!!

BTW - Great lens isn't it !!!