30d AF point selection question

I'm having great difficulties obtaining a decent focus using center point under low light-sporting events. I do plan on having Canon check calibration, I also see my focus point is off quite a bit due to fast movement of subject and slow response by me. I also have seen where subjects are very sharp at times even though focus point is off alot?? My daughter has another sectionals game this Friday! Lucky for me, it's going to start earlier during the day (rain forcast though) I was thinking of trying "all focus points" hoping to improve my in-focus shots...what's the concensus on this? I'm shooting in Manual f/1600 1/400-1/500 shutter in AI Servo.

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What sport?

Volleyball?

hortonsl62 wrote in post #4185961
What sport?

Volleyball?

soccer, added example above, notice focus point yet other subjects look great? I get this quite alot!
Now here is one which has all subjects sharply in-focus, yet my focus point is in between them on the background? Yet it worked? Hit & Miss!

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slyone wrote in post #4186044
soccer, added example above, notice focus point yet other subjects look great? I get this quite alot!
Now here is one which has all subjects sharply in-focus, yet my focus point is in between them on the background? Yet it worked? Hit & Miss!

have you done any focusing tests with consistent lighting?

Codegrinder wrote in post #4186356
have you done any focusing tests with consistent lighting?

I just went back and checked some summer league soccer shots which wereall during the day and they seem fine. Soooo, I can't use my new 30D at night/low light, 2. My camera is messed some how or user error- or a combination of above?
This has really frustrated me since I bought this camera specifically for this season's school sports which is now coming to a close, yet my results have been less than stellar
I tell my kids "have patience" that's what I have to have..lol! Cause I know by spring this issue will be resolved or I'll be shooting with an upgraded body.

Here's 1 that I was tracking towards me 1/3 of the field...?
Tv(Shutter Speed)1/400Sec.Av(Aper​ture Value)F2.8/Metering Modes Spot
Exposure Compensation 0/ISO Speed 1600/Lens EF70-200mm f/2.8L USM
Focal Length 200.0 mm/Image Quality RAW/Flash Off/White Balance Auto
AF mode AI Servo AF

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ive had trouble with my 30d focusing on black with low light too even at f2.8, but im still a noob so i place my camera not working on me.

edit. i see in the second picture her shoes are focused. maybe the lens needs to be looked at?

A few weeks ago I shot an offroad race. I usually use center point AF only. For that race I used auto AF selection and depended on AI Servo to do predictive AF and my keeper rate went up a little. My keeper rate was already pretty high using the center AF only. I can't explain all of your shots. The last one looks like the AF might have locked on the stripes on the field. I don't know about the first one though.

The same thing happens to me. Since august I have the 30d and from day 1 some pictures (not all) seemed to be off focus. I use the same setup as you do (center focus point).
Now, after a great deal of shots, I noticed that the camera has a weekness for the brightest spot in the picture frame and tends to focus on that. Since this is not always in the middle the focus is off.
I see alot of 30d threads with front-back focussing problems and IMHO they can probably point out a software construction problem with the 30d. There has not been a software update since version 1.0.5
Maybe my perception is completely "off" and am I forgetting to change a setting or two or maybe I'm just clumsy but seeing all these similar threads it's probably usefull to do more tests.
Greetings from Ghent
Alain,

At least WRT your second example, you do realize that the little red box doesn't exactly correlate to the AF sensor area. It's about the center of the area, but the AF sensor extends beyond that, and AF will lock on whatever's contrastiest. In the second shot, especially, the AF area actually reaches the player on the left.

Maybe I'm just expecting to much given my novice abilities and lack/luster conditions. Also the fact mt eyesight is lacking (I don't wear my glasses when shooting) I adj. the diopter w/out glasses which is way off w/glasses...that being said, I suppose maybe when hunting (AF) I sometimes wait for clear focus and shoot which actually may be OOF if I had my glasses on?
I was thinking of maybe practicing some more tonight at the field if there's an event happening so I might gain some strategy for tomorrow nights' game.

The first picture appears like the lens was still hunting for focus, since the player closest is in focus, which would seem indicative that the lens was moving through the focus range. In that example, having all focus points would have helped.

You do know that you can quickly toggle between your selected single focus point and all focus points via a signal button press by setting a custom function? I have the middle point set, and select it by clicking on the joystick, and if I hit the focus point selection button, it toggles to all points. This way you can switch quickly back and forth to find the best shot in bad conditions.

Looks to me like in the second shot the camera is focusing as it's supposed to. As Jon mentioned, the actual AF area is larger than the box. The player on the left offers a nice high-contrast thigh for the AF to lock onto.

-js

Thanks Jon and others! After some reading on the Canon AF system (and many threads) I feel most if not all of my current issues may be my own error. I probably should continue using center point and become more proficient at focusing. Thanks again!