manual focus..

[puyjapin]

Had my D40 a little while, seem to got in the habit of using it in auto focus....now using manual a bit...when is it most important to use manual?? i find in auto it obviously doesnt always pick up the subject especially if its accros a flat surface near the lens. also what is the diff betwen single servo and normal auto? thx

 

[Overread]

The time to use manual is when auto focus fails to get what you want in focus. Generally I only always use auto focus in macro work and in dark conditions (though in dark conditions its a struggle for both me and the camera).
You might find AF easier if you set your camera to only use a single auto focus point (commonly the centre point - which is also the best to use in lower grade cameras as it is the best and more accurate sensor)

 

[elemental]

I use autofocus when I trust the camera to get the focus right. If I want to make sure it's right, I use manual. With my Pentax lenses (and apparently only with higher-end Nikon/Canon lenses), I can override the autofocus by moving the ring even in AF mode, which is very helpful. Often I'll let it autofocus, and if I don't like what it gives me, I'll shift it myself.

This is, of course, ignoring the time I spend using manual focus lenses, which is probably ninety percent of my shooting right now.

 

[AlexColeman]

Whenever AF doesn't work.
I find that by making a slight adjustment on my 16-85, I point the AF in the right direction under difficult conditions.

 

[Drake]

Only for macro. For general shooting I always use AF as it's difficult to MF accurately with kit lens on my XTi.

 

[Ls3D]

it obviously doesnt always pick up the subject especially if its accros a flat surface near the lens

Are you sure it is a focus issue? This sounds like a narrow DOF caused by a large aperture. Remember the viewfinder uses the maximum aperture of the lens so you can see a bright view, but then the camera stops down to the AV or corresponding shutter speed (etc) to take the exposure. Depth of field preview comes into play about now...

And forgive me if I misunderstood your post or camera's mode of operation/capabilities.

-Shea