I know the gearing on ENG broadcast lenses have a denser pitch than the standard mod 0.8 found on cine lenses, but what is the actual pitch of the gears? Is it the same on all brands of ENG lenses (Canon, Fujinon mainly), or are there variations? This topic includes lenses with B4, B3, C-mount, and 1/2" bayonet mounts.
As far as I remember it is 0.6
From another forum:
0.50M gear Canon Video
0.60M gear Fuji Video - Focus, Zoom
0.40M gear Fuji Video - Iris
My Fujinon 1/2" bayonet mount and c-mount lenses have focus and zoom gears of mod 0.6. The iris gear is mod 0.4.
On my 1/2" Canon bayonet mount lens, the zoom and focus gears are mod 0.5 , and the iris gear is mod 0.4.
On my old Canon 2/3" c-mount lenses, the focus, zoom, and iris gears are all mod 0.4.
To calculate the module ("mod"), take the circular pitch (mm per tooth measured on the pitch circle) and divide by Pi. http://www.metrication.com/engineering/gears.html Follow focus gear pitches are usually expressed as mod.
It looks like you're new here. If you want to get involved, click one of these buttons!