Seems like a great tool, I have a sigma 30mm 1.4 AF lens, I was wondering if it'd work with it, or which lens mount I would need to get?

Seems like a great tool, I have a sigma 30mm 1.4 AF lens, I was wondering if it'd work with it, or which lens mount I would need to get?


it will work as long it can go into manual mode and the nikon mount will work with it .

Are You sure You have Sigma 30mm 1.4 AF? I'm not sure such exist for SLR's. Quite general is Sigma 30mm F1.4 EX DC HSM. Which is for DSLR's (DC in the name points it). Thus have smaller image circle.
Lens for SLR have - 45mm (36x24)
Lens for DSLR have - 20mm (22.7x15)
Redrock's frame size - 22x16(i'm not sure here, correct me if i'm wrong)

Image circle fits little bit too precisely. It means You may experience vignetting problems. DOF isn't not so..o shallow as well but at 1.4 won't need shallower.

well this is the lens i have http://www.sigmaphoto.com/lenses/lenses_all_details.asp?id=3300&navigator=6, so you think i'd have vignetting problems?


ps: im using a dslr at the moment (canon 20d)

there is small range 35mm SLR lens by what is vignetting minor problem. I think most of us are experienced that. Especially if You use full frame GG(36x24). If You use academy frame(as i think RedRock does) is that problem pretty much reduced. Because You use smaller screening area and vignetting artifacts remain behind the edge of the frame. But You got new problems which are wellknown in photography area - You have to multiple Your focal length. As far DSLR sensor has pretty same size as academy frame then You got to multiple Your 35mm SLR lens FL with 1.6. You don't have to multiple given Sigma lens FL because it's designed similar area. But problem is You find yourself in difficulties to find good wide angle there. Because for instance with 28mm FL lens is now 45mm. 28mm would be nice intro to wideangle but 45mm is in the middle of portraits.
Back to vignetting - i think most of movie makers use in post compensation masks, You can do it as well.