Canon 40D Burst Rate in AI Servo

What's the condition and charge level of your batteries?

I had a few batteries that wouldn't hold charges well back when I was using my 300D/30D/40D bodies and low battery level is one of the things that can slow down continuous shooting. I could see a weak old battery possibly showing enough charge after focusing in one shot but voltage dropping down enough to slow continuous shooting while Ai servo is running.

I know my 1DIV the drive mode icon will flash if battery level is low enough to slow drive speed, maybe the 40D will do the same(manual doesn't same anything about it and I'd test but my batteries for it are fully charged).

I just took my 40D out to try it, in case my memory had failed me. But no, it fires away about twice as fast on high speed continuous mode as it does on low speed. Which is the way it shoud be, since low speed is rated three frames/s and high speed just above six. The important thing is of course that the rate is identical in One Shot AF as it is in AI Servo AF. But I have a nice egde of a white wall against a dark building to focus on, and that house isn't moving fast, to say the least.

The lens in my case was an EF-S 17-85 mm f/4-5.6 IS USM, exposure mode Av, ISO 64o, 1/800 s, f/4. Canon BG-E2N battery grip with two BP-511A batteries inside.

Under conditions that are easy for the AF, I'd say we can be 100% sure that the 40D should be able to maintain full continuous drive speed even when set to AI Servo AF.

Many thanks for that, mine is about 5.5fps so I might just have to live with it!

Harry

Note that the time must be 1/500 s or shorter.

LightRules wrote in post #16649054
Hi there,

I hope you find your answer to this important question.

But let me warn you. These folks here at POTN are ruthless, barbaric, and will never let you off the hook for this sort of question.

TRUST ME!

Never trust anyone who says trust me.

MDJAK wrote in post #16656506
Never trust anyone who says trust me.

......

MDJAK wrote in post #16656506
Never trust anyone who says trust me.

Oh, I think we can trust him on this one.