Lens speed - Wikipedia, the free encyclopedia Lens speed refers to the maximum aperture diameter, or minimum f-number, of a photographic lens. A lens with a larger maximum aperture (that is, a smaller ...
What is a Fast Lens? - Digital Photography School 'I keep hearing about 'fast' lenses and how great they are, but I'm not sure what they are and why I need one. Is it something to do with how fast its shutter speed ...
