just looking for a simple explanation (i think that's the only kind my mind will understand!); it seems so counter intuitive. i'm looking around for a "cheap" lens that's good for low light situations and so i naturally look at lenses that have something like a f/1.4, thinking that this is "better" than one that is, say, f/4.

and yet, while reading thru a number of posts, i read comments by people who are quite knowledgeable that the best shots are achieved when one "steps down" a stop or two. to my mind, that's puzzling. obviously i'm wrong but in my mind, if i want as good a shot as possible, i want _as MUCH_ light as possible, esp in a low light environment.

so am i incorrect in assuming that a lens that has a f/1.4 is going to be better in low light situations vs a lens that's, say, f/4 (assuming we're talking about comparable lenses, not a cheap prime vs an L lens)?

if it's a very sunny day and i'm shooting outdoors, sure, i can understand stopping it all the way down to control the amount of light coming in...

anyway, thanks for any explanations that will clarify this mystery for me ;-)