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07-10-2015, 03:10 PM   #16
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QuoteOriginally posted by clockworkrat Quote
Show us your face!
If you so demand it... Images are being uploaded right now.

—DragonLord

---------- Post added 07-10-15 at 07:08 PM ----------

Pentax K-3 II with DA 50mm lens. HyP-Av, 1/30s f/4.0 ISO 400. AF 27-point Auto, top right of array.


Full Exif metadata is available in the original file on Flickr.

—DragonLord


Last edited by bwDraco; 07-10-2015 at 04:10 PM.
07-10-2015, 07:44 PM   #17
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QuoteOriginally posted by danny09 Quote
But again please show us at least a dozen exif-intact pictures that support your claims.
... the data bytes reserved in EXIF could also be misrepresented by exif reader softwares
Sheesh. This is not a court. He is under no obligation to do anything.

And any K-3 user can download Exiftool, make some photos, and check the EXIF themselves.
07-10-2015, 07:52 PM   #18
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QuoteOriginally posted by rawr Quote
Sheesh. This is not a court. He is under no obligation to do anything.

And any K-3 user can download Exiftool, make some photos, and check the EXIF themselves.
True, it is not a court, but some pretty specific claims are being made on this thread with no supporting evidence presented. I would have expected to see examples of both positive and negative (no face present) with annotated extract from the exif explaining how the conclusions were arrived at.

I suppose I might want to see what is happening here since I did the work some months ago and was unable to find definitive evidence that face detection was at work at all in other than live view.


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07-11-2015, 01:11 AM   #19
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Sadly, I am not convinced that the camera is actually doing face recognition, especially focusing on the eye, when what it is focusing on is a flat photo, with an eye almost right in the centre of the frame. There is no three-dimensionality to show that it is focusing on the eye, the ear, or the tip of the nose, nor is the camera saying "I can see you, hiding in the corner!"


I use centre spot back button focusing only, so it's only a matter of interest for me, but I would like to see test shots with the appropriate eye in various areas of the shot. Face recognition would certainly help when it's selfie day in the SingleIn challenge!

07-11-2015, 08:58 AM   #20
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To clarify, which body, which firmware?
07-11-2015, 03:13 PM   #21
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K-3 II, firmware 1.00.

—DragonLord
07-15-2015, 07:20 AM   #22
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maybe Pentax is learning the Face Detection on Fuji X-T1
If the K3 can do this, the next FF will definitely nail it
07-15-2015, 08:13 PM   #23
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QuoteOriginally posted by DragonLord Quote
Inspired by "https://www.pentaxforums.com/forums/172-pentax-k-3/271999-k-3-multisegment-me...-smart-me.html".

From my own testing, I can confirm face detection exists when shooting through the viewfinder. If the autofocus system is set to Auto 27 or Auto 9, and the Real-Time Scene Analysis System detects faces in the frame that are within the AF area, it will use the focus point closest to the subject's eye. The camera will also adjust the exposure accordingly. The detected face(s) is reported in the Exif data, and up to 5 faces can be detected in viewfinder shooting (checked using ExifTool).

Questions, thoughts, or comments?

—DragonLord
I hate to disagree as much as I would love for the K-3 to have this technology. I did a quick and dirty test like your test shooting your photo, only I used a photo with two people in the scene. The auto focus was set up exactly like you set yours and try as I might there was no consistent autofocus eye selection or face recognition that I could find. Exif Tool did report face detection but only one face. In live view, however, two faces were detected and were reported in Exif Tool as two. After that I focused on a portrait with no people in the scene and EXIF Tool reported a face detection based on the EXIF data. So I believe your methods were flawed. Tell me where I went wrong?

07-16-2015, 12:44 PM   #24
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Experience shows that the technology isn't perfect. It'll try to detect faces, and if large enough, attempt to focus on the eye, but it doesn't always work. It's likely due to the limited resolution of the metering sensor (360x240). The amount of light available also affects the effectiveness of face detection.

—DragonLord

Last edited by bwDraco; 07-16-2015 at 02:20 PM.
07-16-2015, 06:46 PM   #25
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QuoteOriginally posted by DragonLord Quote
It's likely due to the limited resolution of the metering sensor (360x240). The amount of light available also affects the effectiveness of face detection.
The resolution of the K-3 imaging sensor may not be as great a limitation as you suppose.

The Nikon D610 has a mere 2016 pixel (2k) metering sensor, and yet in PDAF can still detect faces. (Proof of that is easy to see with the D610, since it can immediately highlight detected faces upon image playback on the rear-screen).

Detecting eyes and assigning them priority as focus targets is harder, but probably doable with the rich information coming in from the K-3's RGB sensor, due to it's very high resolution and -3EV sensitivity. Face detection algorithms are pretty smart nowadays.
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