40d Af

Saabo King · 20th December 2007

Hi,

I realised that my 40D uses 9 different zones for AF. But I realised that sometimes it does not focus on the object I centered on but focus on the parts out of the centre.

So now I switch to single middle focus point only. Would like to ask what is the uses for the 9 point focus?

jeff49er · 20th December 2007

Sounds like you were using autofocus, correct?

Tumbleweed · 21st December 2007

If you plan to pictures where the subject is off center, then you would probably set the focus point to where the subject is.

If you're taking portraits than it would be best to set the focus point to one where it is closest to the subject's eye. You can still use the center focus point but you need to recompose after focus has locked onto the eye. Using a focus point out of center would reduce the amount of camera movement during recomposition especially if you like taking lots of portrait shots.

There are many other possibilities of using any 9 of the focus points. It is up to situation and your imagination!

20th December 2007	#1
Saabo King Member Join Date: Sep 2007 Posts: 147	40d Af Hi, I realised that my 40D uses 9 different zones for AF. But I realised that sometimes it does not focus on the object I centered on but focus on the parts out of the centre. So now I switch to single middle focus point only. Would like to ask what is the uses for the 9 point focus? __________________ 5D, 28-105mm F/4-5.6 USM, 50mm F/1.8 II, 580 EX Mk II,Tamron 28-75 f2.8

20th December 2007	#2
jeff49er Senior Member Join Date: Apr 2003 Location: Punggol Park Posts: 2,020	Re: 40d Af Sounds like you were using autofocus, correct?

21st December 2007	#3
Tumbleweed Member Join Date: Mar 2005 Location: Woodlands, Singapore Posts: 226	Re: 40d Af If you plan to pictures where the subject is off center, then you would probably set the focus point to where the subject is. If you're taking portraits than it would be best to set the focus point to one where it is closest to the subject's eye. You can still use the center focus point but you need to recompose after focus has locked onto the eye. Using a focus point out of center would reduce the amount of camera movement during recomposition especially if you like taking lots of portrait shots. There are many other possibilities of using any 9 of the focus points. It is up to situation and your imagination!