I think I need to cut my teeth on the GH2 before looking at the AF-100
Philip Bloom sings the praises of the Tokina 11-16 (in Nikon F mount) which has a constant aperture of 2.8.
Despite the loss of autofocus and the increase in size over the MTF lenses, does anyone else use it for video?
I use this lens on my GH2. It is a very nice lens but a big lump, and it is not very well balanced because the MFT-F mount adapter make it protrude a lot. It has a 77 filterthread but I haven't used any filters on it yet because of its big protruding front lens element. Furthermore, for my lens I need a MFT-F mount adapter capable of controlling the aperture, since when mounted on a Nikon camera the aperture is controlled from the camerabody. Maybe Philip's lens is an older version with mechanical aperture control.
In general it is much fun to be able to put al these nice legacy lenses on the GH2, be it Leica M/R. Nikon, Canon (old FD's are very nice), Zeiss (C/Y), etc.