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Photosopher View Drop Down
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 21:29
Originally posted by stiuskr stiuskr wrote:

(no more than 60p and less is better)


Yes 120p disengages face detection, and although tracking still works, it is compromised when using wide AF and letting the camera pick the object. Better to use specified AF point when shooting 120p. Still pretty good on a99II though, on which I can't see any difference in face detection performance between 24, 30, and 60p. And 120p works great with specified AF point.

Yes I use the technology. But only for moving subjects, or when camera is moving along with subject. This short reel clip Is combination AF/MF. Should be obvious which shots benefit from it and which shots it is completely unnecessary.

Edited by Photosopher - 15 March 2019 at 21:33
 



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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 21:43
Originally posted by Photosopher Photosopher wrote:

Just out of curiosity, with all the effort spent on watching videos and corresponding with Dyxxum etc... Have you watched any of the How To Talking Head videos I linked? Have you practiced any manual focus? Have you looked into the camera manual?



Somewhat, however my main concern since I came across this problem a few days ago was to determine what is causing it. Thanks to input like yours I am not as confused about that as I was.
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 21:46
Excuse me if the question has been asked and answered, but what lens are you using?
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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 22:00
Originally posted by Photosopher Photosopher wrote:

Excuse me if the question has been asked and answered, but what lens are you using?


In this case, Sony Zeiss FE 35mm f2.8 (in aps-c crop mode)
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Photosopher View Drop Down
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 22:53
That's right, I remember now. And I believe you stated that you were shooting it at f4... Is that correct?

If so, I suggest the only thing that accomplished was to cripple your AF system by one f-stop. The depth of field difference between f2.8 and f4 will be negligible. And shooting crop mode makes up for that d.o.f. difference anyway. E-Mount AF tracking benefits greatly when used wide open.

Also, check your AF menu options for stickiness. Set to "Locked On" rather than normal or responsive. This will help camera stay on target without jumping to background or hands so quickly.

Otherwise, turn on focus peaking (try medium), get a good set of reader glasses, and practice some manual focus.

Consider that it is much much much much more acceptable for a subject to be seen moving out of focus plane a bit (here and there) than it is for any clip to show focus hunting from automation. Tell your talent to get comfortable in the position they will be speaking from, and not move around while talking. That's not an unreasonable request. Not only is it better for the focus plane, but it's more aesthetically pleasing to the viewer to have the speaker hold still.
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Post Options Post Options   Quote jkp1 Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 22:55
I guess this hunting have nothing to do w face detection or not. Seen the issue in other scenes as well...
Unused stuff in stock: A700, 24-105, 28-135, Sony A100, beercan, 100-200, Sony 70-200f2.8 + teleconverter
 



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Photosopher View Drop Down
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Post Options Post Options   Quote Photosopher Quote  Post ReplyReply Direct Link To This Post Posted: 15 March 2019 at 23:17
Originally posted by jkp1 jkp1 wrote:

I guess this hunting have nothing to do w face detection or not. Seen the issue in other scenes as well...


It's a compound. It shares a piece of the pie simply by taking more processing power. But so does light, camera generation, AF tech, lens choice, and probably even how well the subject matches Sony's perfect face detection algorithm. My ex-wife looked less than human in the morning. Face detection didn't work very well on her.
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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 16 March 2019 at 01:07
Originally posted by Photosopher Photosopher wrote:

My ex-wife looked less than human in the morning. Face detection didn't work very well on her.


Maybe the problem I ran into was also something to do with the hour of the morning? But in my case I suspect it was more to do with lack of coffee than the appearance of the subject.

However it did seem to work ok on Peter Gregg's poodle.
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Post Options Post Options   Quote windhorse Quote  Post ReplyReply Direct Link To This Post Posted: 26 March 2019 at 21:44
Now here is an interesting contribution to the on-going discussion about face detection autofocus, and how it is effected by using other in-camera focus aids and/or external hdmi monitor.

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Post Options Post Options   Quote QuietOC Quote  Post ReplyReply Direct Link To This Post Posted: 08 June 2019 at 18:35
I did a 50 Mb/s 24p XAVC-S image quality test today on my cameras.

Using Tamron SP 35mm F1.8 USD stopped down to f/4. No Lens Compensations. SteadyShot disabled. White Balance set to incandescent.

Lowest ISO available: ISO 200 on the A7II and ISO 100 on the A68, A77II, and A6000.

I verified that setting Sharpness to -3 is required to remove sharpening halos on all the cameras. This is also true for JPEGs.

The A68 has the least moire and the best resolution. I repeated the test a few times to verify that. I hadn't found a sharpness difference in raw stills capture, but the video capture is cleaner on the A68, but there is some purple fringing on the A68 that is not as obvious on the other cameras.

The APS-C video mode on the A7II is awful. Almost like Sony takes a crop of the full-frame video mode. There are still large edge halos even at -3 sharpness. The full-frame mode on the A7II looks better than I was lead to believe. It is just a bit worse than the A6000.

A6000


A77II


A68


A7II


A7II APS-C


Edited by QuietOC - 08 June 2019 at 18:42
Sony A7II A77II LA-EA3 LA-EA4 MC-11
Minolta Maxxum 600si
Pentax Q7 5-15 15-45/2.8
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