Focus points selection

Hello,

as mentioned in my introduction, I have upgraded to a D7000 and have a couple of general questions about autofocus selection:

- when to use AF- A S and C?
- when to use single point, 9 or 39 point autofocus?

The manual is great in that it tells me HOW to select the different options, but does not tell me in which situation I would select what. A quick explanation would be greatly appreciated.

Thanks in advance for your help.
Martin

I would strongly recommend that you get Darrell Young's "Mastering the D7000" or a similar book. He explains pretty well how these options can be mostly beneficial and when to use them.

Explaining all this subject in this forum would just take me too long and is something of a personal taste. What works for me might not work as well for you. My D7000 is almost always set to single point AF-S. I will focus on the square and then recompose to take the shot. I've also set the menu so that the camera won't fire if the focus is not acquired.

Hope this helps a little even if it doesn't explain it all.

This is a nice write-up. It's been shared around here a lot:
http://www.pixelfinesse.com/_docs/D7000_AF_Explained.pdf

Englischdude said:

Hello,

as mentioned in my introduction, I have upgraded to a D7000 and have a couple of general questions about autofocus selection:

- when to use AF- A S and C?
- when to use single point, 9 or 39 point autofocus?

The manual is great in that it tells me HOW to select the different options, but does not tell me in which situation I would select what. A quick explanation would be greatly appreciated.

Thanks in advance for your help.
Martin

Click to expand...

The manual does explain it well, without mystery.

D7000 page 91 (also see next page)

AF-S For stationary subjects. Focus locks when shutter release button is pressed halfway. At default settings, shutter can only be released when focus has been achieved.

AF-C For moving subjects. Camera focuses continuously while shutter release button is pressed halfway (predictive tracking to follow moving subjects). At default settings, shutter can be released whether or not focus has been achieved.

My bold part seems kind of a big deal. IOW, there are options, but if shooting in burst mode, AF-C might find focus on the second or third frame, but AF-S is the right choice for almost anything else except motion.


Live View is different, cannot follow motion, half press locks focus. Page 50.


Focus area (focus points) Page 95

Single point - for stationary subjects (really no other way to describe this, but it is most pictures)

9 point - motion, but when there is time to focus
21 point - sports
51 point - flying birds, etc

I wanted to point out the A3 setting. Pay attention to this setting when experimenting with AF-C. It defaults to introducing a delay into continuously focusing that can be confusing when you are trying to learn how af-c works. I keep my A3 off, but you may want it on in some situations. An example would be if you are panning some action with trees or people's heads popping briefly into the viewfinder. Adding a delay will momentarily delay the camera from trying to re-focusing on someone's head or other distractions that may quickly come and go.

I went through a lot of the same type of questions after getting my D7000. You will find lots of posts/thoughts about focus modes on this site. Play around with the different modes and see how each reacts in different situations. If I have something that I know is not going to move, then I use AF-S; which also is handy to me for focusing and recomposing. For moving subjects, I'm going to start experimenting with AF-C 9-point (I've also set in on focus priority for now to see how it works out). I've read the pixelfinesse guide and also just purchased David Busch's book on the D7000.