I use a 24-70 mm USB L series lens on my rebel Xti with a compact flash. Can I use the same lens?

[Skirball]

On what camera?

I assume you mean the 24-70 USM?  That's an EF lens, it will fit on any EOS camera, but requires an adapter for EOS M.

[Carnac]

Yes you can use the 24-70 L on a Rebel. Nice lens.

The lens has USM (ultrasonic motor) focusing, not USB.

Compact Flash is the type of storage card your camera uses - has nothing to do with the lens it will accept.

Your Rebel will work with any Canon EF or EF-S lens.

The EF 24-70L will work on any Canon EOS camera. The new mirrorless Canon EOS M requires an adaptor to use EF or ER-S lenses.

Jim