This is a quick non-scientific comparison video of several lenses. I compared the kit Lumix 14-140 lens to the following:
Canon FD 28mm F2.8
Minolta 35-70mm F2.5
c-mount 35mm F1.8 CCTV
c-mount 25mm F1.2 CCTV
Canon c- mount 11-70mm TV
the c-mount lenses used the SLR Magic adapter.
The subject is a wine glass, lit with 5600K daylight LED light source and the room was lit with 2800K CFL lights. The camera was white balanced for day light.
The GH1 is using the Ptools firmware hack and was shooting 24FPS no pulldown 1080P at 40Mbs with a 1/50th sec. shutter.
Edited as ProRes 422 in FCP. Output to h.264 @400Kbs