This is an interesting conversion which on the surface addresses some of the frustrations with using Canon Lens on the FS100.
So what do they do?
Firstly they take your existing 70-200mm Canon lens and remove the IS module so that they can fit end stops to the lens. Then they also add a manual Iris control ring. In additional they then add 0.8 pitch gears to the iris, zoom and focus to give a more Cine feel. (they can also modify the 16-35mm and the 24-70mm)
Certainly in principle this seems to make sense but in reality I'm not as convinced.
Certainly having a manual iris is a big plus as that's how I'm used to exposing with traditional Cine Zooms and Broadcast TV lenses. The action is smooth and the pitch gears help also when operating.
The end stops are not a deal breaker for me. I'd rather keep image stabilization for those times when you grab the camera and go hand held. And when I spoke to Octica in the UK who lent me the lens they indicated that it might be possible to leave IS in and lose the end stops so it certainly seems to be an option.
The other main concern is that when focusing at the long end of the focal length there's still not enough real estate to pull focus effectively. So while the physical mod helps it still only partly solves the issue.
Cost of Mod is £2495 +VAT (approx $4k) which is a bit of a gulp if you're moving up from DLSR but less of a gulp if you're moving down from Cine lenses. But this is not a cine lens so I question if it is a valuable modification.
For me I'd rather buy a dedicated zoom. However options are non existent currently. But with NAB just around the corner I'd be hoping that lens manufacturers are recognising the need for affordable cine style zooms and maybe well see some options in April.
Here's a short video review of the technical Farm lens. For more info you can email Spencer or Tony at Octica firstname.lastname@example.org
They're looking for feedback and interested in what you think so feel free to email them.