The rolling shutter effect on the GH1 varies with the frame rate. The 1080p 24fps mode is clearly the worst. The 720p mode 60fps is a LOT better. The 720p 30fps MJPEG mode is somewhere in between. I tested by shooting the sweep arm of a metronome. Rolling shutter does not seem to vary based on shutter speed. I can imagine that there may be similar variation with other cameras. Hi I tried to invent