I apologize for not finding this answer on my own, as I'm sure it is out there somewhere, but I figured it would be easier just to ask and be done with it.
I understand that a fast lens will let you shoot with a faster shutter speed when wide open, but my question is this:
Let's say I have a 5omm f/1.8 and a 50mm f/1.2. If I set BOTH of them to f/8, will the 1.2 allow me to use a faster shutter speed? The aperture would be the same, but the surface area of the glass would presumably be bigger on the 1.2 lens. Does that make a difference, or are you only gaining something when shooting wide open (or at a bigger aperture than what is available on the 1.8 )?