We've been talking about a few fast lenses in other threads, and I said I'd run a more structured test of the focus characteristics for some of my fast lenses. Below are the results. All were shot wide open. I wanted to get an idea of the characteristics of the focal plane, drop-off, etc. so I could understand how to best use these lenses at wide open aperture. Hope they're helpful to others as well.
GH1; ISO200; 1/200 to 1/400 shutter; wide open aperture; natural window lighting; JPEGs as shot from camera w/ minimal PP
Target provided by Tim Jackson: Focus Test Chart v2.1
Canon FD 50/1.4
Canon FL 55/1.2