I also just got a 15 mm fisheye, but on my 5d3, the image does not fill the frame. In post with the LR lens profile, I seem to lose quite a bit of the image during cropping. Any suggestions?
Sorry but I am afraid that you are incorrect. The Canon 15mm f/2.8 Fisheye Lens is for full-frame cameras and the image circle completely fills the frame of a 5D Mark III as it is a full-frame camera.
The thing with a fisheye is that you do not use it often...but when you see the shot...nothing else will work!!!...that is the fun and the challenge....the lens makes YOU hunt for the image that does the lens justice! It's not for everyone.....but I love mine!
I shot this with my MFT fisheye...(yes...I own two! Lol!)
It's grainy, but i like it.
Added the muted colors and grain in post prod. On purpose. Thanks!
5D Mark III, Canon 15mm f/2.8 Fisheye, Canon 16-35mm f/2.8L II, 21mm f/2.8 Zeiss, Sigma 35mm f/1.4, 24-70mm f/2.8 II, 50mm f/1.4 Sigma, 85mm f/1.2L, 100mm f/2.8L Macro,70-200mm f/2.8L IS II...1.4x converter III, and some other stuff!