24-105IS and 30D center point focus ?

kini62

On the 30D the center point is "high precision" only at 2.8 or better.

How does this affect the AF with the 24-105?

Is it less accurate of sensitive? Any problems with this combo?

Thanks again for the help.

Gene

ivar

kini62 wrote:

On the 30D the center point is "high precision" only at 2.8 or better.

How does this affect the AF with the 24-105?

Is it less accurate of sensitive? Any problems with this combo?

Thanks again for the help.

Gene

I've got no idea what 'high precision' means. But when I focus with this lens, I don't have any problems with it. Not for any af point btw. It's fast and sharp, that's the way I want it.

Tee Why

I believe on a 30D, with a f2.8 or faster lens, it will AF faster.

LiquidAir

Higher precision focus is required at wider apetures because of the shallower depth of field. The center focus point has an extra high precision sensor that kicks in on fast lenses to get the accuracy required when the DoF is very thin. The real message to take home is at f/4 all the focus points are accurate enough for the DoF, but at f/2.8 or wider only the center point is accurate enough to handle the shallower DoF. When shooting wider than f/4 you should force your camera to only use the center AF point.

I have the 24-105 and I have never had AF problems with it. However with my fast primes I do see the limitations of the outer AF points.