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General discussion

Canon Digital auto focus time?

by ethrapp Nov 13, 2010 7:12AM PST

What is the time required for the Canon Digital Rebel to focus? Is the T1i any faster? I do a lot of ambient light photography in high school gyms shooting basketball games. The time it takes to focus is a problem. Are other cameras faster?

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6 Posts
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Autofocus
by PistonCupChampion Nov 13, 2010 7:36AM PST

Autofocus is dependent on the lens. The standard kit lens sold with Canon cameras is quite good, but it's not very bright; the maximum aperture is only f/3.5 at 18mm, and f/5.6 at 55mm. Indoor basketball is going to tax the autofocus with that lens. A different camera won't make a big difference, but a brighter lens will.

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Canon Digital auto focus time?
by ethrapp Nov 13, 2010 7:32PM PST

I should have included more info in the orginal question. I am using a Canon Digital Rebel camera, an 85mm 1.8f lense and a 400 iso. The depth of field is so narrow that it is difficult to get good, in focus, pictures of fast moving basketball players. By the time the camera is focused, the player has moved more than the depth of field. I have been unable to find what the auto focus time is for this camera and was wondering if newer models or other makes,had a faster response time.

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In that price range
by kalel33-20416052469708587370302374692233 Nov 13, 2010 11:43PM PST

You'll find that the Rebel is a very fast focusing camera. What focusing mode are you shooting in? Sports takes practice at becoming good at. You should be using AI-servo, with the center-point as the capturing focus and once locked then using expansion to continue tracking if the player moves outside of the center. If you just try to shoot the player in "One shot" then you'll have poor performance with any camera.

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Focusing Mode
by PistonCupChampion Nov 13, 2010 11:56PM PST

If you are shooting in full auto, then the camera will be using all the focus points. That could be something other than what you intend. The above advice is sound.

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Also
by kalel33-20416052469708587370302374692233 Nov 13, 2010 11:47PM PST

What kind of shutter speeds are you getting? If you get 1/500th or faster shutter speeds at 400ISO then look at bumping it up to 1600ISO so you could move the aperture to something along the lines of F4. You are extremely lucky to get fast shutter speeds in a high school gym using 400ISO. I've never been to a gym that didn't at least require 800ISO to get 1/400th of a sec.

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Focus Mode
by ethrapp Nov 14, 2010 2:39AM PST

The gym I'm presently shooting at is pretty well lit, my shutter speeds vary from 320-640 typically. As I mentioned I'm using a fixed lense 85mm, 1.8f. As you pointed out, I think my problem is that I have haven't been using Al-servo, I don't know why. I don't like to use 800iso because the pics get grainy. I'll use Al-servo next week and see how that goes, thanks

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