drogi1 wrote in post #7848449
I am really interested in the canon 10-22mm lens.But, doesn't canon have a similar camera with,let's say,2.8f ? Is 3.5f enough?
Ultra wide angle lenses like the 10-22 are niche items, and most users do not need fast ultra wide. Making this lens a bit slower (the lens is really f/3.5-4.5) makes it smaller, lighter and more affordable.
and also, no lens like that , which is ef? (Thinking about upgradind to full-frame in the future and ef-s lens will not work)
Keep in mind that on a FF camera like a 5D a 20mm lens is already ultra wide. The absolute widest Canon EF zoom lens is the EF 16-35/2.8. Note that at 16mm on a FF camara this lens offers the same extreme wide angle for FF that 10mm does on 1.6X.
In essence, the EF-S 10-22 was designed to offer an ultra wide lens option for Canon's 1.6X shooters. To make it EF (FF compatible) would make it something else entirely, and the price would be several times as much.