2 Focus questions. AF-ON vs. shutter release.

Started Jan 30, 2013 | Discussions thread
Jim Keye Senior Member • Posts: 1,899
Re: 2 Focus questions. AF-ON vs. shutter release.

Martin Grecner wrote:

asultan wrote:

I will probably switch to AF-ON only since slight movements on the shutter release screw up focus all the time

What do you mean by "slight movements on the shutter release" ?

I believe he means that if you (accidentally) let up pressure enough and then reapply it, you trigger the autofocus to stop/start.

This becomes an issue in either mode. In AF-S, if you've recomposed, then of course re-triggering the AF would cause it to refocus where the sensor now is. In AF-C, if you're trying to track, then stopping the AF causes the tracking to stop and then needs the time to reacquire focus and/or resume tracking.

That's one advantage to the AF-On button, you can mash it with your thumb and there's no confusion as to hard you're pushing it, accidentally triggering the shutter, etc.

When you hold the shutter button half-pressed, it does exactly the same as if you hold the AF-ON button pressed, as far as I am concerned...

Yes, it should. It's just a lot easier with a separate button.

Keyboard shortcuts:
FForum PPrevious NNext WNext unread UUpvote SSubscribe RReply QQuote BBookmark MMy threads
Color scheme? Blue / Yellow