Don't do it. I owned that lens for a year and like Landis said the lack of filter threads makes it essentially useless for filming skiing. If it was sunny out I would have to shoot at like f22 and 1/500 and the footage would look terrible. I tried to build a filter holder for it but it vignetted up to around 10mm anyway, so I decided fuck that and bought a nikon mount 11-16. The Tokina is a nicer lens overall anyway. I like the extra weight since the GH2 is so light on a Glidecam, and the character of it is just much more pleasing. The Panasonic lenses have a very harsh, clinical look to them IMO.