There was recently some debate here about whether C-mount video lenses can deliver good results on M-4/3rds cameras. I have a few of them that are at least as good as cine lenses (the Pentax 25/1.4 comes to mind), but I recently acquired the crème de la crème of all video lenses: a series of Zeiss Tevidon lenses comprising the 35/1.9, the 50/1.8, 75/2.8 and 100/2.8. All of them are outstanding lenses, providing a sharp image, even wide open, without vignetting and chromatic aberrations and with superb colors.
Here are some samples from the 100/2.8:
100% crop from previous image, note the water droplets in bright sun against a dark backgroud without a trace of purple fringing:
Wide open at F/2.8:
And now, the 35/1.9 lens:
Wide open at F/1.9:
Not too shabby, uh?