Quote Originally Posted by Ron Kruger
If you have better glass, letting in more light, it doesn't just let in more light at f2.8 appature, but at f11 as well.
Well, no.

Ron, as Sushigaijin, Grandpaw, and OldClicker have been trying to tell you, f/11 is f/11 is f/11.

Consider this thought experiment: you have two lenses - a 200mm f/1.8 and a 200mm f/4

Set each at f/11 - the SAME AMOUNT OF LIGHT will come through. The exact same shutter speed will be used.

Otherwise, utter chaos will envelop the universe.