Diagonal fisheye

[Fedgrub]

I can't decide what to get. Can anyone help me decide?

I want a diagonal fish eye for my 5Dmkii. I'm not too interested in getting the circle look where the black makes the subject trapped in a circle, I just would like the distortion at the edge of the frame.

I was looking at the Canon 8mm-15mm f4L fisheye for $1290 but that only fills the frame at 15mm.

The Sigma 15mm F2.8 EX DG Diagonal Fisheye is less than half it's price at $603.

I've never used Sigma before and all my lenses are Canon, so I'm reluctant to buy anything but Canon until I know what I'm getting myself into. I'm leaning towards the Sigma because I won't be using the fisheye as often as my 24-105mm or my 100mm f2.8 Macro, but I'm not sure whether it's worth forking out the more for the Canon L. Is it much sharper?

Has anyone used this lens before or had any experiences they'd like to share about Sigma?

Thanks

Matt

[Bennymiata]

Is sharpness all that important in a fish-eye lens?

I'm sure the Sigma is pretty sharp, and considering you won't be using it all the time, I'm sure the Sigma will do a great job for you.

As fish-eyes have huge DOF, and focussing is not so important, you could also look at the Rokinon (and it's other re-branded versions) which will be much cheaper still, but they are manual focus lenses.

[fabian628]

canon 15mm f/1.8 is quite good IQ. resistant to flare very well, centreal sharpness at 2.8 is very good also.

[Tannin]

Tokina 10-17 fish. Versatile, viceless, delightful Pentax-designed optics, excellent Tokina build quality, fairly reasonable price, vastly more flexible than fixed length units, what's not to like. The Tokina 1-17 isn't the best choice, it's the ONLY choice!

[Tannin]

^ cancel that post. I thought you had a 50D. The Tokina fisheye works brilliantly on APS-C and can be used (sort of) on APS-H, not FX though. For my 5D II, my fisheye lens of choice is a Tokina 10-17 on a 50D - 'cause there is nothing worth having in FX fisheye lenses: there are various primes (what is the point of a single focal length in a fish, which is highly specialised as it is, never mind restricting it to a single FL?) and the ridiculous Canon thing - which is also effectively a prime as it turns into a useless circular fish when you zoom out.

I believe that Pentax used to make a 35mm zoom fish back in film days and that the Pentax/Tokina 10-17 is a scaled down version of it. I'd love them to bring it back!

[Fedgrub]

Thanks for the feedback, everyone. Went with the Sigma because I found it pretty cheap.