Sony A1 A1 (human) eye-AF - Eyelashes or pupils ?

[Reciprocum]

3 out of 4 were eyelash focused

AF-C, human detection, close to MFD for the lens, wide open (f1.8) A-priority, subject not moving.
Focus area was Spot-S dead smack in the pupil ...

• ILCE-1
• Sony FE 135mm F1.8 GM (SEL135F18GM)
• 135.0 mm
• ƒ/1.8
• 1/250 sec
• ISO 100

• ILCE-1
• Sony FE 135mm F1.8 GM (SEL135F18GM)
• 135.0 mm
• ƒ/1.8
• 1/160 sec
• ISO 250

• ILCE-1
• Sony FE 135mm F1.8 GM (SEL135F18GM)
• 135.0 mm
• ƒ/1.8
• 1/160 sec
• ISO 250

• ILCE-1
• Sony FE 135mm F1.8 GM (SEL135F18GM)
• 135.0 mm
• ƒ/1.8
• 1/160 sec
• ISO 320

 

[AlphaWorld]

Why would you have your depth of field so shallow that one or the other is blurred? If I am photographing a human, I would be standing back a little so I can get both eyes in the shot, and depth of field should get the eyes and eyelashes in focus. That would also let the eye AF algorithms recognise that it is looking at a face, and therefore focus on the eye.

Can you show us the whole frame? I wonder if you were so close that the eye AF was unable to recognise it as an eye?

 

[garuda]

I would try both AFC & AFS; and at f5.6 w both eyes in frame.

 

[Reciprocum]

Why would you have your depth of field so shallow that one or the other is blurred? If I am photographing a human, I would be standing back a little so I can get both eyes in the shot, and depth of field should get the eyes and eyelashes in focus. That would also let the eye AF algorithms recognise that it is looking at a face, and therefore focus on the eye.

• ILCE-1
• Sony FE 135mm F1.8 GM (SEL135F18GM)
• 135.0 mm
• ƒ/1.8
• 1/250 sec
• ISO 100

Totally standard framing and shooting distances. Daughter was watching cartoons and quite still so I knew this was the perfect opportunity to make a scientific(ish...) eye focus benchmark. I tried AF-C & AF-S, same results.
Indoors available (window) light so I have to shoot as wide as the lens allows (I prefer to stay at iso100 especially now with the A1).

"I wonder if you were so close that the eye AF was unable to recognise it as an eye?": I was using Spot-S focusing area, it does not have to recognise anything, it just has to focus where I have that spot on (dead smack in the center of the eye), and with AF-C it just has to keep trying (120x/sec as per the specs) all the way till the shutter button is fully depressed ...
For me is a clear fail as there is no sharper (or faster focusing) lens than the 135mm GM (E-mount system off course ) and no better AF system than the A1's

Then again maybe we should interpret this as an Spot-S failure and not attribute guilt to the eye-AF ?

 

[AlphaWorld]

I think you are onto something.

Would you agree that Spot S, used alone, could legitimately lock onto eyelashes? After all, that's how those conventional focus systems work - lock onto the object in the focus area which is closest to the camera. Admittedly, most lens / camera systems would ignore the eyelashes because they couldn't "see" them, but this combination can

If you get a chance for another experiment, try doing it again with a larger focus area, like, say, Zone. I think that would give eye AF a chance to recognise the eyes and focus on them the way it is meant to.

(BTW: I agree, the 135mm f/1.8 GM is an extraordinary lens, screamingly fast, and exquisitely sharp - I thoroughly enjoyed Roger Cicala's assessment of it over at Lens Rentals https://www.lensrentals.com/blog/2019/03/sony-fe-135mm-f1-8-gm-early-mtf-results/ , and his teardown showed how beautifully designed it is inside: https://www.lensrentals.com/blog/2019/06/disassembling-the-sony-fe-135mm-f1-8-gm/ )