[Rookies]

I am trying to decide how to work the AF points on my canon 400d

As i dont really understand it fully.

If I have the left focus on a tree the rust of picture be blurred right so how do i do a long DOF?

[Tobers]

Long DOF is related to aperture. If you have a large aperture (low F-number like F4) you get shallow DOF so the background is blurry. If you make the aperture smaller (like F16) you get deeper DOF so foreground and background are sharp.

You can tweak the aperture easily in P mode my twiddling the wheel behind the shutter release. Try taking a number of shots of the same thing at different apertures and see what they look like. The exif on each shot will show you what the aperture was when you took it (see it in Zoombrowser simply).

The focus points are where the lens focuses. It will try and figure out where to focus and in auto-mode will sort this out itself. I almost always shoot in manual mode (P generally, but aperture and shutter priority quite often, and rarely full manual). I set it to only use the central focal point (hold button on back & twiddle knob on top), I'll focus on the subject and then reframe as required whilst holding the shutter release half-down.

Make sense?

Tobers

[Rookies]

Originally Posted by Tobers

Long DOF is related to aperture. If you have a large aperture (low F-number like F4) you get shallow DOF so the background is blurry. If you make the aperture smaller (like F16) you get deeper DOF so foreground and background are sharp.

You can tweak the aperture easily in P mode my twiddling the wheel behind the shutter release. Try taking a number of shots of the same thing at different apertures and see what they look like. The exif on each shot will show you what the aperture was when you took it (see it in Zoombrowser simply).

The focus points are where the lens focuses. It will try and figure out where to focus and in auto-mode will sort this out itself. I almost always shoot in manual mode (P generally, but aperture and shutter priority quite often, and rarely full manual). I set it to only use the central focal point (hold button on back & twiddle knob on top), I'll focus on the subject and then reframe as required whilst holding the shutter release half-down.

Make sense?

Tobers

Yup I am with you on this :D will give this a try tmr