ed rader wrote in post #16470286
I beg to differ. 21mm is certainly UW.
While you are technically correct that traditionally on a 35mm format sensor less than 24mm lens is considered ultra wide, but I am going out on a limb and guess that the OP is talking about something much wider here: closer to 14-17mm as suggested in the opening post. As you know comparing FoV of 21mm and 14-17mm is quite massive difference...
CanonYouCan wrote in post #16471402
I need the AF, so no Samyang, time that they start developping also lenses with AF.
Probably the Sigma fisheye, I like compact primes with sharp IQ.
Edit: Almost did not see your response here, silly me.
Anyway, I can't stop but to wonder how unwilling or lazy people seem to have become these days. It's seen as a serious disadvantage that you have to manual focus a ultra wide angle lens, while I see it exactly the other way: I would never trust autofocus system to achieve that critical focus on landscapes, or if the focus ring has actually been designed for a long focus throw it's much more pleasurable to use (e.g. Zeiss and Samyang focus rings are excelent imo). And autofocus lenses tend not to have a hard stop at infinity, a feature which I never liked, and manual focus lenses usually do have (Sure there exceptions here, I know...). In addition UWA lenses are so easy lenses to focus anyway, basically at 14mm f/8 focus to 3 meters and everything will be in focus to infinity (well, almost).
Good luck in your decision