Originally posted by jremick Most of the time my kit lens does just fine since I'm outside but I find myself in hikes where it's getting dusk or the lighting is less than ideal for fast moving situations.
OK, but realize that with larger aperture comes shallower DOF, and that's another enemy of fast moving action. There's really no getting around the fact that if you want to stop action in low light, flash is the real answer.
Not that there is no place for fast lenses, but I just don't want you thinking that shooting 50mm and f/1.4 is going to solve these problems - it won't. There are reasons most sports photographers use f/2.8 zooms, not faster primes.
Quote: I usually have the space to move relatively freely so I can adjust my distance from the subject as necessary, so 50mm would be fine (I think).
Shooting from far away with a 50 is not the same as shoot from closer with a wide angle - the perspective is totally different. Yu mention jumping between rocks. As it happens, I've got a shot like that taken last week with my DA15:
Had I shot this from further away with a 50, then in order to get the jumper the same size in the frame I'd have only been able to fit in roughly 1/4 as much of the surrounding scene. Chances are I could not have fit both the rock he was jumping from and the one he was jumping to in the frame at the same time without backing up far enough that he was smaller in the frame than he is here.
Now, I'm not saying that my shot above is exactly how you'd want your shots to look, but the point is, changing position has a very real effect on the picture, and you can't simply assume that a given focal length will work just because you have room to change position. You really do need to give thought to focal length.
Quote: But, in addition to that, I'd like to have a better lens to shoot indoors (people, animals, etc.) and from what I've gathered a fast 50mm (or close to it) would be a good choice.
If you've gathered this from your own experience with your kit lens, fine - but most people would say 50mm is far too long for casual snapshots on APS-C. it was great for this on film, but on APS-C, you want something with a similar FOV - meaning something in the 28-40mm range.
Quote: Plus, I've read lots of fun things to do with a "nifty fifty", which I'd like to try.
Now, that *is* indeed the case. Given that you can get a great manual focus 50 for about $50 or less, I do think everyone should have one - but one shouldn't expect it to be one's go-to lens for situations where it isn't really well suited.
So what I'm saying here is that you really want the 50 *and* some other gear - probably a good flash for the low light action shots, but perhaps a wider angle
"fast enough" lens like a 16-50/2.8 or just a 24mm or 28mm prime.