c.d.embrey said:
The ONLY thing that Canon announced today that I'd be even half-way interested in. What advantages will it have over my EF-S 10-22 f3.5-4.5? Cn I use it at 8mm without vignetting on an AS-C camera - why wasn't a simple question answered in the press release?
I think Canon's intended customers are FF body owners, who would now have a circular fisheye & diagonal fisheye in one.
Per my understanding of the press release, you would have vignetting on APS-C at 8mm, and that there are markings on the lens indicating at which focal lengthes would APS-C & APS-H sensors get the equivalent of a diagonal fisheye.