This unscientific test was setup to determine the effect of doing a "focus lock, recompose, shoot" (FRS)manouver unsing the 550EX speedlite in E-TTL mode and the camera in M mode. Camera settings were f11, shutter speed 1/100, ISO 100. The center focus point is manually selected. In each shot, I used the manually selected center focus point to cover my subject. After achieving a focus lock, I recomposed the shot to what you see here and took my shot. The red crosshair show approximately where my center focus point ended up after the recompose. Interesting huh?