If I edit a photo on my camera roll on an iPhone 13 running iOS 16.6, everything seems to work except noise reduction. I have it set to 100% in Portrait Mode. Looks fine until I select Done and then this is reverted.
iPhone 13 Pro Max
This probably doesn't help; I edit pictures on my Mac, so I don't have much experience. But I just tried it on my 12pro, also with iOS 16.6, and noise reduction sticks for me. Revert goes back, just as expected.
Does this happen when you edit in Photos, or just when you edit from the Camera app?
Has this been happening all along, or is this a new behavior? What might have changed? Have you tried restarting your phone?
This happens editing taken photos in the Photo App.
photo edit noise removal not saving on iPhone
