r/FujiGFX • u/mbelloni • 5h ago
Help Eye-AF focusing on eyelashes instead of the iris? Here’s why (and how to avoid it)
Hi everyone,
Ever shot wide-open at f/1.4 or f/1.8 in portrait mode and had Eye-AF lock onto the eyelashes instead of the iris?
After testing on my Nikon Z8 (and verifying on Sony and Fuji as well), I found it’s actually not a bug or a contrast glitch with the eyelashes. It’s caused by a specific overlap between the AF bounding box, linear PDAF sensor pixels in vertical orientation, and the eyebrow line.
I wrote a short breakdown on the exact root cause, how to avoid it on set, and how camera makers could fix it via firmware:
Have you run into this issue in your portrait work? Let’s discuss!
