Focussing with that 85mm...

Hey y'all,

I've been shooting sports recently, mostly bball cause that's what's in season...and using my lovely new 85mm f/1.8, which seems to be surprisingly popular for sports shooting.

My question is, how much of the time are your images wildly or oddly out of focus...? I shot about 200 images the other night and of those about 38 or so were focussed correctly, and most of those were images of players not really moving...

Am I doing something wrong?

Settings have consistently been f/2.2, 1/640, and ISO1600...I go back and forth between AI Servo and one shot (or whatever it's called)...tried the thing where all the focus points are lit up, it wasn't particularly helpful...heh.

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[QUOTE=J.Lynn.R;729769​0]...tried the thing where all the focus points are lit up, it wasn't particularly helpful...

Nice captures! You could try shooting with only the center focus point lit and I think your "keepers" will increase, and maybe venture up to f2.0 as well.

For basketball and the 85 lens, I always shoot 2.0 -2.4. So you should be ok there.

Also shoot center point and use the back button for focus. Remember you must hold the button in to maintain a focus on the moving target.

if you are shooting at f/1.8 the depth of field on that lens is so fine that you can easily have an object in focus and then have that focus change to the background really easily.

just keep it at f/2 and use AI servo and center focus point.

you should be fine with that

If you are using the XT in your signature, that could be some of the problem. I went from XT to XTi to 40d recently and each camera was better than the one before it (in terms of ability to correctly focus). The XTi gave me about 50% success and the 40d is hitting about 90% of the time (in dark gyms). I use the 85 1.8 in AI servo, center point.

George

lauderdalems wrote in post #7297976
Also shoot center point and use the back button for focus. Remember you must hold the button in to maintain a focus on the moving target.

This feature is new to me. Can you explain or point me to what it is called in the manual for this setting?

(BTW, I am using the XSi with the 85.. f/1.8 to shoot indoor swimming)

Custom Funtion 4.1 (Uses the * button for focus, and is highly reccomended)

J.Lynn.R wrote in post #7297690
Hey y'all,

I've been shooting sports recently, mostly bball cause that's what's in season...and using my lovely new 85mm f/1.8, which seems to be surprisingly popular for sports shooting.

My question is, how much of the time are your images wildly or oddly out of focus...? I shot about 200 images the other night and of those about 38 or so were focussed correctly, and most of those were images of players not really moving...

Am I doing something wrong?

Settings have consistently been f/2.2, 1/640, and ISO1600...I go back and forth between AI Servo and one shot (or whatever it's called)...tried the thing where all the focus points are lit up, it wasn't particularly helpful...heh.

Looks like you have some room to play with your settings there. 1/640th seems excessivly fast for basketball, you could probably get away with dropping it down almost a stop and either increasing your f-stop to 2.8 for more depth or bringing your ISO down. The XT line is pretty fuzzy with high ISO's so that might be part of it.

AI Servo & Center point focus are probably the way to go too, as previously mentioned.

Having said all that, I have have to say I've never shot basketball I do shoot a lot of fencing though, and even with the thin, fast moving blades I find 1/500th to be plenty fast enough and can often get away with less.

Just play around a bit, you'll get there in the end!

George E. wrote in post #7302370
If you are using the XT in your signature, that could be some of the problem. I went from XT to XTi to 40d recently and each camera was better than the one before it (in terms of ability to correctly focus). The XTi gave me about 50% success and the 40d is hitting about 90% of the time (in dark gyms). I use the 85 1.8 in AI servo, center point.

George

I was wondering about that...shoot! Well I can't afford a different body at the moment, I'll just have to be more careful. I've noticed focus problems when doing portraits as well...I can deal with it though.

Looks like center point and AI Servo is the way to go...will set that back button next time I go to shoot sports.

Like Souporman said, maybe you could try 2.5 or 2.8, but more than likely you're probably just slightly off on your focus point. I had the same kind of problem until I made myself really concentrate on keeping the center focusing point right on the upper chest of my subject at all times. A couple of other things to keep in mind are that it's a little more difficult when focusing on white uniforms (seems like the lens wants to grab something in the background with a little more contrast) and when the subject is coming right at you.

I don't wish to hijack the thread, but I have another question regarding the back button focus option.

Why is that any different than holding the shutter halfway? If I am using manual exposure, (as I usually do in a gym) then it seems to me that the 1/2 shutter is only focussing- which would be the same as the back button. The shutter, however, gives me one less button to press- it seems simpler.

It has been suggested many time to use the back button for focus with sports, so maybe I am missing something- can anyone explain?

souporman wrote in post #7303154
Looks like you have some room to play with your settings there. 1/640th seems excessivly fast for basketball, you could probably get away with dropping it down almost a stop and either increasing your f-stop to 2.8 for more depth or bringing your ISO down. The XT line is pretty fuzzy with high ISO's so that might be part of it.

AI Servo & Center point focus are probably the way to go too, as previously mentioned.

Having said all that, I have have to say I've never shot basketball I do shoot a lot of fencing though, and even with the thin, fast moving blades I find 1/500th to be plenty fast enough and can often get away with less.

Just play around a bit, you'll get there in the end!

I disagree with this. 1/640 is not extreme for basketball and in my opinion is the low end of acceptable. Do everything you can to keep your shutter speed as fast as possible.

While the DOF of the 85 is pretty thin, the gains from stopping down the aperture are not as major as you might think. Wtih the 85 shooting from 20ft away your DOF is as follows: At f/1.8 - 1.13 feet. At f/2.2 - 1.42 feet. At f/2.8 - 1.79 feet. So, going from 1.8 to 2.8 only increases your total DOF by 8 inches and this is spit between front and back.

The other option that I have not seen mentioned is that your lens and camera may need to be calibrated together by Canon. If you are consistently getting OOF images under a variety of conditions, this is a likely cause of the trouble.

sfinkernagel wrote in post #7310538
I don't wish to hijack the thread, but I have another question regarding the back button focus option.

Why is that any different than holding the shutter halfway? If I am using manual exposure, (as I usually do in a gym) then it seems to me that the 1/2 shutter is only focussing- which would be the same as the back button. The shutter, however, gives me one less button to press- it seems simpler.

It has been suggested many time to use the back button for focus with sports, so maybe I am missing something- can anyone explain?

Shooting manual, there is no difference. This is a personal style thing and does not offer any technological advantage when shooting fully manual exposure.

Big K wrote in post #7312071
While the DOF of the 85 is pretty thin, the gains from stopping down the aperture are not as major as you might think. Wtih the 85 shooting from 20ft away your DOF is as follows: At f/1.8 - 1.13 feet. At f/2.2 - 1.42 feet. At f/2.8 - 1.79 feet. So, going from 1.8 to 2.8 only increases your total DOF by 8 inches and this is spit between front and back.

The other option that I have not seen mentioned is that your lens and camera may need to be calibrated together by Canon. If you are consistently getting OOF images under a variety of conditions, this is a likely cause of the trouble.

.

That is an incredibly useful bit of information. I will definitely make sure to remember that...

Actually, that sounds incredibly likely...I've taken several sets of portrait shots with odd focus problems lately...totally don't have the money to have it done though, neither camera nor lens are under warranty.

I used to shoot bball with that basic 75-300 lens (f/4-5.6, I think?), and I always got better results with manual focusing. Is that worth a try with the 85mm?

J.Lynn.R wrote in post #7313290
I used to shoot bball with that basic 75-300 lens (f/4-5.6, I think?), and I always got better results with manual focusing. Is that worth a try with the 85mm?

It would be worth a try but I am afraid you would be disappointed with the results. Your other lens, since it is f/4-5.6 was probably more forgiving regarding DOF which is what allowed you to get some good results.

You might check on the cost to get it calibrated. It might not be as bad as you think and if that is the problem, it will save you lots of frustration.

Good luck.