Posted 29 November 2010 - 05:51 AM
Although the camera does not have a dedicated AF-ON button, you can assign the AF-L/AE-L to be AF-ON, which at the same time disables the AF function of the shutter. This works in both normal shooting and live view and it is a good way to shoot in live view - stopping the focus from hunting and giving you a push to focus function. However, we found it has too much of propensity to hunt to use it during filming while shooting video. As Peter says you can also hear the button being pressed on the video! For stills it is fine - as you wait for it to be focused then shoot.
Would it not be valuable to use AF-ON or half press the shutter for video in a similar fashion to that you describe for stills, simply to fix chosen points of focus, essentially using autofocus as a way to focus manually rather than relying on one's eyes to judge whether the picture on the screen is in perfect focus or not. I ask this because I have a hard time with a videocam underwater judging focus on the screen. This seems to work for me topside. On camera sound underwater is of fairly limited use, recording mostly the sound of scuba bubbles. If sound is important adding an external hydrophone would be better would it not?
Edited by loftus, 29 November 2010 - 05:52 AM.
Nikon D800, Nikon D7000, Nauticam, Inons, Subtronic Novas. Lens collection - 10-17, 15, 16, 16-35, 14-24, 24-70, 85, 18-200, 28-300, 70-200, 60 and 105, TC's. Macs with Aperture and Photoshop.