Even High Quality Preview Not Matching Output

I noticed some extreme artifacts in an exported photo just now, that appeared to be related to detail or structure settings. Viewing at 100%, it looks like a 3rd-degree burn scar on the side of the subject’s nose and under his eye… This is somehow the result of editing, as the student has no such scar. But because the preview does not show the artifacts, I am unable to determine what edit to undo to correct it.

On review in DxO, the photo seems fine, even with high quality previews turned on. So I re-exported to both .dmg and .jpg quality 95. The result was the same and in both export files. No issue with the preview, but a significant patch of artifacts in the exports.

To create an apples-to-apples comparison, I screenshot the preview from DxO and then screen shot the .jpg as rendered, both at 100%.

I have edited thousands of shots and never noticed this before. Does anyone know how to get an accurate preview in this odd case…

The Preview:

The Export:

Hi Jeff,
could you share the file to let me try – here or via PM?
As far as I can see it is already in the (less sharp) preview.
Wolfgang

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Only HQ noise reduction is shown in the image preview at 75% zoom or greater. PRIME NR is only visible in the exported image or in the loupe tool that is part of the NR palette.

Be aware that this setting has nothing to do with what you see in the image preview. It only concerns what you see while you are dragging an adjustment slider.

I hope that helps.

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I don’t have PL6 so I’m not familiar with DeepPRIME XD noise reduction but if you are using that, then from what I’ve read here that feature can introduce artefacts.

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DeepPRIME XD can sometimes interpret facial features such as scars etc and make the look unfaltering. Best way to avoid this is to dial down the amount of noise reduction or play with other settings if one is using PhotoLab 6. If one is using Pure RAW maybe best to use Deep Prime the older version which will probably be less aggressive over this.

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The only preview you’ve got in your case is the small denoising window prewiew.
If you’ve got a high pixel count camera it is maybe 1/1500 the size of your image (really not usefull. Very sorry for you !!!).
And more than that, it will deactivate about everytime when you’ll tweak a tool, so you’ll have to activate it again.

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Mostly you should stop using DeepPrime XD and use DeepPrime instead. DeepPrime XD works well enough on buildings and even landscapes but the human eye is very sensitive to changes to faces and skin texture. The XD part basically creates detail, sometimes creating awful artefacts (as in this case). If you’d like to preview these artefacts, the best way is by creating full size exports. You can check specific parts of an image (faces for instance) using the preview window in the NR section.

Another advantage of DeepPrime is that it’s about 3x faster than DeepPrime XD, hence creating full preview versions is much less of a burden. I upgraded to PhotoLab 6 for the improvements to Local Adjustments and the repair tools so in this case I don’t mind that DeepPrime XD is more a marketing trick than a reliable feature. But that’s what it is.

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Thanks all, for filling me in on the details of how HQ previews and DeepPrime work. This will lead to some big improvements in my work.

Good explanation. It seems that Prime, DeepPrime and DeepPrime XD all actually create this artifact to some degree. You are right that DeepPrime may be the best starting point for most photos. Here is a comparison from no noise reduction, then High Quality through Deep Prime XD. I’ve noticed these artifacts before, but confused it with a structure or microcontrast issue. This has been very helpful.

Raw from Sony A7IV, Tamron 35-150 f/2.2-2.8 @ 52mm, f/2.2, 1/640th, -1EV, ISO 3200

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Did you try to lower lens sharpness ?
I found it is set most of the time too much high at the new default value (=1), and I generally put it to 0 and sometime less.
This oversharpening generally produce some “artefacts” on the images I do.

Lens_sharpenss

And what I see on your images is that the boy certainly does not have burn scar, but seeing the first image you provided, its skin has some little “imperfections” - or whatever you want to call it - at the place where “burn scars” appears.
So I think you should try to lower lens sharpness to see if it does something to your problem.

I can see some signs of oversharpening on other parts of your image.

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I got bright yellow artefacts on white cloth on images that have been taken under low light and color spotlights (concert condition). I found no way to get rid of them if the color temperature was anything else than bluish super cool. May this be of same cause?
I will anyhow try not using Deep Prime XD to see if this was the answer.

What you describes looks like oversaturation of some color channels when shooting.
Not sure it is the same than here.

Do you push histogram to the right when shooting in low light conditions ?

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Could be so. Thanks for the comment.

The stage had very sharp and bright light from above and the hairs are overexposed - elsewhere everything was dark and underexposed. Color lights mixed with the whites and the color changed constantly. Different color at different areas in the picture.
Shot at abt - 0.7 to get details in the white shirts. The histogram leaks slightly at both ends - most at the dark.
When I tried to correct the color to uniform along the image, the white shirts got said artifacts. Their shape was not always correlating with the shape of the shirts.
I shall experiment by varying the noise reduction to learn about this.