View Full Version : Blurry subject, sharp background in V-ball - HELP!!!
davidmigl
7th of September 2006 (Thu), 22:21
Hello,
Just returned from a round of volleyball games with ~400 shots. I shot with the Digital Rebel XT (350d) and Mark I f/1.8 50mm. ISO 1600, 1/500, f/2.2. Many of the shots are unusable due to focus issues - the background is tack sharp, the subject, blurry. I was using AI servo with the center autofocus point and when I noticed this, switched to all autofocus points to see if my camera would do any better. Nope. What am I doing wrong??? Is this a matter of the lens not having enough time to focus?? Do I just need to get the 1.2 L 85mm??
Here's an example:
http://img373.imageshack.us/img373/7049/bluryy8.jpg
Thanks for your help!!
David Migl
Jim G
8th of September 2006 (Fri), 04:28
Looks like you've focused behind the subject... the 50mm 1.8 isn't the fastest or most accurate focusing lens ever but it's not too bad... it probably won't be able to keep up with fast moving targets, though, or at least mine didn't. Manual focus may help a little but the 50mm 1.4 or 85mm 1.8 are much faster with the autofocus, especially the 85...
I don't often shoot this stuff, other people may be able to offer more helpful advice :p It's difficult to say prefocus the lens because the 1.8 doesn't have full time manual focus.. it'd probably make it a bit easier...
sando
8th of September 2006 (Fri), 04:33
Focus is way off. Looks to be on the guy in the BG, but even at 1/500s it looks blurred.
Pete
8th of September 2006 (Fri), 05:01
I'd say that the shutter speed is fine. The ball's not blurred, it's bokeh'd.
Not that I'd done any sports photography, I'd say that f/2.2 would give a depth of focus that's far too small, you'd end up with arms and legs that would be out of focus if they were more than a couple of feet in front of or behind the focus point.
I'd think it's because the AI servo can't copy with this kind of situation, it's more geared toward cars, planes moving in a predictable, smooth action. The AI server is probably overcompensating here and can't deal with quick changes of direction. Normal, multipoint AF would probably have been the best option here..
Chimping every few shots would have helped saved the majority of the shots as well.
liza
8th of September 2006 (Fri), 05:33
I shoot gym sports quite a bit using the 85mm f/1.8 and the 100mm f/2. Both are great when shot two stops from wide open. I use AI Servo and center point focus for all my sports shots. It just takes patience and practice to get the focusing down in situations with fast action. The Digital Rebel's autofocus is also a bit slow for sports so you need to work on timing to compensate.
davidmigl
8th of September 2006 (Fri), 08:06
Thanks for the tips and information - I had a hunch that it might somewhat be my equipment. I'll just have to practice some more, but fortunately this might be an excuse to upgrade to the 1.4 or 85 (hehehe...)
TheSteveMadden
8th of September 2006 (Fri), 16:36
If the focus point wanders for just an instant, it WILL latch onto the contrasty background. I've learned to "see" the AI Servo focus plane and hold off when focus wanders.
I shoot gym sports quite a bit using the 85mm f/1.8 and the 100mm f/2. Both are great when shot two stops from wide open.
Liza, when you say two stops, do you really mean that or did you mean two clicks (2/3 of a stop) Two stops would be f/3.5 or f/4 with those lenses, wouldn't it. Maybe my definition of stop is wrong :???:
In2Photos
8th of September 2006 (Fri), 16:41
Liza, when you say two stops, do you really mean that or did you mean two clicks (2/3 of a stop) Two stops would be f/3.5 or f/4 with those lenses, wouldn't it. Maybe my definition of stop is wrong :???:
I was thinking the same thing. I always here about how bad gym lighting is and how you need a fast lens for this environment, but shooting at f/4 could be done with a lot of lenses. Perhaps just a slip of the ol' typing fingers.
Gary_Evans
8th of September 2006 (Fri), 16:48
Why not manually focus? Most of my togs prefer to work this way.
IMO, you'd be better off spending your money on a faster focussing body, before you spend on an L series lens.
Mike Reynolds
8th of September 2006 (Fri), 17:12
this looks like your POF (Point of Focus) was set on the big whistle blower in the center of your photo. Use the little red focus dot in your viewfinder and your POF will be where you tell it to be.
symes
8th of September 2006 (Fri), 17:25
in a dark setting like that gym the 50mm 1.8 is tough but the 85mm 1.8 I hear is dynamite...
I work alot in the gym's around campus and as other shave pointed out...first you haven't nailed the focus...second you have a slow focusing lens especially in low light...
you certainly need a new lense for that type of photography...unless you prefocus to a point and wait
davidmigl
8th of September 2006 (Fri), 19:23
Cool, thanks for the interesting tips... What lens/body is preferred for indoor volleyball/basketball?
I assume that the 50mm 1.4's USM autofocus would leave my current lens' autofocus in the dust? And that the 85mm 1.8 would be just as fast as the 50 1.4 when it comes to focusing, while adding some needed focal length for v-ball and b-ball? Right? (Can't you tell I teetering on the brink of a decision lol...)
symes
8th of September 2006 (Fri), 19:32
Cool, thanks for the interesting tips... What lens/body is preferred for indoor volleyball/basketball?
I assume that the 50mm 1.4's USM autofocus would leave my current lens' autofocus in the dust? And that the 85mm 1.8 would be just as fast as the 50 1.4 when it comes to focusing, while adding some needed focal length for v-ball and b-ball? Right? (Can't you tell I teetering on the brink of a decision lol...)
actually the 85 1.8 is much faster to focus...even faster than the 1.2 L by most accounts...
Cheers,
liza
9th of September 2006 (Sat), 13:27
Liza, when you say two stops, do you really mean that or did you mean two clicks (2/3 of a stop) Two stops would be f/3.5 or f/4 with those lenses, wouldn't it. Maybe my definition of stop is wrong :???:
Two clicks.
DavidW
10th of September 2006 (Sun), 17:10
Two clicks is 2/3 stop - not two stops. Those sort of apertures would make sense to me.
David
Tandem
11th of September 2006 (Mon), 08:58
I shot a volleyball tournament Saturday using the 85 f/1.8 at f/2.2. It was the first time outside of my f/2.8 comfort zone and I was very pleased with the results. The narrow DOF wasn't as much of an issue as I thought it would be.
SuzyView
11th of September 2006 (Mon), 09:14
Narrow dof is hard on sports. I manual focus a lot when shooting indoor sports or events. Makes life a lot easier than having the camera try to focus with action so quick. AI Servo or AI Focus?
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