I recently bought a second-hand Carl Zeiss Jena PANCOLAR MC 1.8/50mm Lens off eBay (still waiting for it to arrive though) and am going to mount it to my Canon 7D via a M42 adaptor. I primarily shoot video and am not a fan of high ISO so I thought the 1.8 would be a good way to go.
My mate has a similar lens, but in the 2.8, and he reckons that the images won't be as sharp because of the larger aperture.
Can anyone explain why this might be? And how noticeable it may be?