asamimasa wrote in post #13002130
I'd say the 85 1.8.
Sigma's 1.4 offering is nice and focuses fast enough, but you probably won't be shooting 1.4 for sports, as the thin DoF will result in a lot of missed shots. The few people I know who shoot sports and occasionally pack the Sigma 85 would stop it down to 1.8 or even 2.8 so that they could keep focus.
Sooooooo
The 85 1.8 I'd say is what you want. The focusing is absolutely superb.
50D, 85mm, and a subject 15 feet away, that DOF is thin, but 1.4 vs 1.8 vs 2.0 vs 2.8 doesn't make all that much of a difference!
1.4 = .5 ft
1.8 = .6 ft
2.0 - .7 ft
2.8 = 1 foot
If you double the distance (30 feet), the DOF is 4X those numbers... for most sports, indoor or outdoor, unless that sport is darts, you'll be at least 15+ feet away from your subject, and that subject isn't likely to remain that close to you.
The DOF argument is a weak one for this scenario
I haven't had the opportunity to shoot hockey with the Sig85 yet, but that's coming. I always step down as much as I can while still maintaining fast enough shutter speed to stop the action. If the light is bad enough that I need wide open, then 1.4 is better than 1.8
One of the biggest bargains in the Canon lineup is the 85mm 1.8. Light, bright, fast, and very very affordable.
It's great for indoor, outdoor and outerspace (or so I'm told)
If you need to let in a bit more light, and not sacrifice too much in AF speed, the Sig85 is the next step up.
The Canon 1.2L Mark II is pretty good in AF as well - the real issue is once it loses focus, the hunt from 1 end to the other is very slow (relative to just about anything else). I've used it for hockey a few times, and there's no issue with tracking/following a player in any direction. If you decide to switch which player you're focused on, acquiring the next one might be slow if the lens needs to hunt through the whole range, but once you have the player, you're ok.
