Some labels came from the pictures alone. We still have the samples, but those labels aren't tied to physical inspection results. That's irritatingly circular

Mark those labels uncertain and have the samples inspected properly. Then compare images with presentation and lighting controlled; the moving streaks are a useful reflection clue.

@NathanBaker0460 A scratch's visibility can change with presentation too. Don't let 'moving streak' quietly become the rule for relabelling something acceptable.

Correct. I meant a reason to investigate the imaging, not a new defect label. Physical acceptance stays with the agreed inspection method.

@NathanBaker0460 So uncertain isn't the same as good? Where do those images go?

Retain their sample identities and undecided status. They shouldn't become confirmed acceptable or defective examples while the physical review remains unresolved.

Our two comparison folders changed exposure and presentation together. I can't tell which change made the images look better. That comparison needs a caveat too

I had a separate inspection setup where the 'better lighting' folder used easier samples too. Its name implied a lighting conclusion that the comparison didn't support.

What did you keep beside each image? I can manage sample ID and settings, but I don't want a form nobody fills in

For my separate setup, sample identity, exposure, lighting arrangement and presentation condition were the useful essentials. They let us understand comparisons without relying on recollection.

Use those details to ask your vision specialist for controlled comparisons on representative surfaces. Keep the sample set fixed when assessing an acquisition change.

Would a learned model just cope with the lighting differences?

Any learned model still depends on reliable labels and representative evaluation. Changing the method doesn't resolve unconfirmed physical defects or an uncontrolled comparison of image conditions.

@NathanBaker0460 And don't tune and test on different pictures of the same physical sample. That isn't the independence the result would suggest.

@NaomiAllen0332 I've settled the review method: physical reference checks plus controlled image comparisons. That answers where to start; whether our inspection concept is suitable still depends on the resulting evaluation

That gives the evaluation a sound question to answer. Suitability remains dependent on those checks, as you've made clear.