I decided to try something crazy and different on the D7000, back button focus.
The usual setup for auto focus on a camera is the half press of the shutter button. This also determines the exposure. What back button focus does is remove the auto focus trigger from the shutter button and move it to a button on the back of the camera.
Why would you want to do this? One reason is that once set the focus stays set, the camera won’t try to re focus each and every shot. If your subject isn’t moving much this is a good thing. Another reason is that you can get the best of both worlds of Auto-Servo and Auto-Continuous. Once you press and release the back button the focus is set as if it was in Servo mode. But if you continue to hold down the button the focus mode continues to focus wherever you have the focus point. Which is the regular continuous mode.
To set a Nikon to back button focus is pretty ease.
- Set focus mode to AF-C
- In the Custom Setting menu Controls set your AE/AF lock button to AF-ON
- Also in Custom Setting menu under Autofocus set AF-C to Release priority. You will not get the beep of focus lock in this mode. Whenever you press the shutter button the camera will take a picture.
Now comes the fun part. Getting used to pushing a button on the back of the camera to focus since you have now told the camera to take a picture, no matter what. This is the stage I am in currently. Supposedly once you get used to it you don’t want to go back to using the shutter button. That is still open for debate.
I will let you know.
Do you use back button focus? What are you reasons for using it or not?
I’m currently trying it for continuous focus shots only, but I’m having difficulty getting used to it. I will probably end up giving up.
I just covered the same topic on my blog. It’s definitely a useful method!