Help me with the math :)

[PhantomVideo]

Hi so i want to put a http://www.kenrockwell.com/tokina/11-16mm.htm on my brevis, I know its not FF but at 15mm it will cover the frame (According to Kenrockwells tests) my question is what will the Focal lenths in 35mm eqvi be so a 15mm DX lens on a brevis and what math would you used to figure it out, if im being insane with the plan wake me up before I go go, also will the lens open up to 2.8 i know it dont have an iris ring im just hoping that it will stay open at 2.8

[Huy Vu]

A DX lens will not work on an adapter. The circle of illumination would be so small that you won't be able to clear it by zooming in and still get a usable image.