are you aiming towards the light source or the camera?
Always hold the meter in front of the face of the subject, aimed toward the camera.
For studio work, I typically shoot with my 17-55 2.8. Not enough time with other lenses to notice trends. It does seem to be consistent between bodies, though (30D and 7D).
It's not a deal breaker or anything. Like anything else, you just learn your equipment and deal with it. I was just curious what your experience has been, that's all.











