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View Full Version : Focus hunt in C-AF


pvasc
18th March 2013, 06:42 PM
Has anybody noticed that when tracking an object the lens keeps minutely adjusting focus, like a heartbeat?

Here's an example. I was playing with C-AF today, the focus would lock onto the object,stay locked and the lens would ever so slightly move in and out. This happens all the time actually, even on non moving objects. My PL1 did it too. The E-30 does not. Is it the way CDAF works compared to PDAF? I'm sure if I were to take a picture it would be infocus because I have the shutter release priority OFF.

Daveart
18th March 2013, 10:46 PM
Hi, this happens to recheck focus as you are in continuos mode, you will find that live view focus is active, this is a feature added for video to keep track and keep in focus posible movement.

Dave

pvasc
19th March 2013, 08:27 AM
Thanks I had a feeling it was something like that because both PENS did it and it didn't go back and forth in and out of focus.

Ian
19th March 2013, 09:28 AM
You might find the FTU Knowledge Base wiki explanation useful:

http://fourthirds-user.com/wiki/Contrast_detection

Ian