I do the opposite. I have a back button on my Nikon set up to lock the focus. I find this accomplishes about the same thing with less time keeping the button held down.

How do you handle moving objects this way? This is not a criticism, I am wanting to try this method while shooting great white sharks in a couple of weeks. The trick for me is to choose a custom assignment that my housing can access.

Quote from: landbysea on September 07, 2013, 12:41

I do the opposite. I have a back button on my Nikon set up to lock the focus. I find this accomplishes about the same thing with less time keeping the button held down.

How do you handle moving objects this way? This is not a criticism, I am wanting to try this method while shooting great white sharks in a couple of weeks. The trick for me is to choose a custom assignment that my housing can access.

The shutter button does the focusing so for moving subjects I can just use the shutter button. But if I achieve a focus I want to keep for a few seconds I just jam the button on the lens side of the camera and it locks the focus. It is very natural and comfortable for me to work that way and involves very little movement while maintaining a good grip.
I corrected my original post because it is a button on the front I have set up not a back button.  I tried the method in the OP , but using a back button is awkward. I much prefer how I do it now and it has most of the same advantages, but not that great for using a remote release, where you might want the BB method to maintain a set focus without touching the camera.

Thom Hogan addresses this in this months teaching article.

http://www.bythom.com/

I think if Hogan had his 10,000 hours in that he refers to he would realize that with that method you are not using the thumb grip properly if your thumb is pushing a button and also has to release tension on said button when focus is achieved, risking dropping longlens and camera into said snow if handholding.  My method requires a very short learning curve, leaves the thumb on the thumb grip and achieves the exact same thing as the BB method. He should have mentioned both ways.