"But what if I got fisheye lens of 7.5 that all manual (apture and focuse). Couldn't it work well enough? Lens that are so wide don't need too much focus" This is what I was thinking The 7artisans 7.5mm for ef-m mount. Sounds like from the previous post link on someones experience it might be no infinity, he also warns electronic lens will be locked at minimum (not maximum) aperture so f/22. But the 7artisans in manual aperture and manual focus. And it's super wide.... So 14mm on a crop body, and a little less extreme...sounds good to me?