Pen F users - some quick questions...

acfo wrote:

Raist3d wrote:

Update: I just checked the shots under the second scenario on the computer (was checking then on the camera in the field under the sun). Yeah, the hit rate was pretty bad wide open (like 75%+ out of focus in some way to bad). With F3.5 I still got misses but some hits. Yeah, I wouldn't call this stellar. I guess the envelope under with the C-AF PenF works well is narrow, and if that's where you do your photography and want this feature then you are set. Not so much otherwise.

First of all thank you for taking the time to experiment and reporting back.

👍

The results are quite an eye opener for me. Previously I had assumed, that cdaf always focuses wide open and the aperture is only set when the picture is taken like pdaf systems do. I've begun to read up on this finding, however there are contradicting views on this matter, e.g. one opinion is that a shallower depth of field should allow the auto focus to determine in focus faster.

Well to be fair now that you mention that, it's simply possible that it works as you said (with the wide open aperture) but the wide open final shot taken vs the smaller aperture shows focusing mistakes, while the other would, but since it has more DOF in the final shot, "hides" the issue.

Obviously the longer the lens the shallower the depth of field wide open. At 300mm - my usual focal length for C-AF - the depth of field can be too shallow for the subject, which is why I step down. This seems to be the sweet spot for C-AF as I can wave around the camera following peewits and still have a very high hit rate.

Lens speed will also matter. I would imagine the Olympus pro tele or the lens you are using has a higher AF speed.