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Old Feb 23, 2012, 10:09 PM   #1
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Default Canon 60D AI Servo Question

I have learned (somewhat belatedly) that AI Servo always begins focus with the center focus point. I gather that the other points come into play to help track a moving subject. That being the case, does selecting only the center focus point vs. leaving all points selected and starting focus with the center point make any difference in the focus operation?
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Old Feb 27, 2012, 4:36 AM   #2
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hi I found this
http://www.shutterfreaks.com/Tips/CanonAIServo.html
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Old Feb 28, 2012, 6:02 PM   #3
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Thanks, but much of this link pertains to the 1DII and not all is applicable to the 60D.
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Old Feb 29, 2012, 3:26 AM   #4
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I think A1 servo works the same principle in canon cameras
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Old Feb 29, 2012, 7:45 AM   #5
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Ropp - the principles are very similar. To answer your question:
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does selecting only the center focus point vs. leaving all points selected and starting focus with the center point make any difference in the focus operation?
If you select a single focus point, the camera only uses that point. So if that point moves off your subject, you'll focus on something else that is under the point. If you leave all points active, the camera will try to detect that the subject has moved from "current" point to a new point. How effective that operation is is always up for debate. That's why for larger subjects most action shooters select just a single point - it takes the camera's "guess worK" out of the equation. Using all points is still useful for small subjects (small flying birds for example that move too fast and erratic to keep a single point on very easily).

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Old Mar 1, 2012, 8:22 AM   #6
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Well that explains why my first attempt at shooting a flag football game came out with almost (95%) of all the pictures were blurry. I'm sure that with some more practice and correct camera settings I will get better results. It's just I never had a camera with more than one focus point until now. Then again, I find the old dial corded phones were much easier to use than todays smart phones.

Edit:
Read the article and will try the suggested settings with my Canon 7D and see what happens. The article made sense, expect for the picture they gave as an example of using AI servo. The picture of the water skier makes no use of the AI servo mode, the skier is holding a rope that is a fix length, the photographer is in the boat so the distance between the skier and photographer never changes. I have taken pictures of many water skiers long before AI servo was invented and never had a focus problem. I can try to put a rope on the flag football players but don't think that will work real well at all.lol
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Last edited by Calicajun; Mar 1, 2012 at 8:57 AM. Reason: Added more words
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