I've never seen this before - crazy green artefacts in the highlights

Processing
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Hi, I’m seeing green checkerboard type artefacts in the highlights in a whole series of .arw files in darktable. The images were made in one session the other day.

The issue doesn’t appear in Macbook Preview or the lighttable thumbnail, only in the darkroom processing view. The green pattern appears in the original data before the processing begins.

The camera is a Sony Alpha 7ii, and the example provided was shot at 1/50 at ISO800 if that helps. Others in the series have a similar problem, shot at lower ISOs and longer exposures as well.

Any ideas? The attached image is a screenshot, because a non-raw export does not show the issue.

Tartan green
Tartan green4032×2688 2.01 MB

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Looks like you have enabled raw overexposure warning…just turn it off…It’s showing blown channels in the raw capture

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Also lots of pattern noise all the way up to Nyquist in the frequency domain.

G’MIC Fourier Transform Magnitude, at 50% GIMP Threshold, then resized 4032 > 1008 wide for posting here:

Tartan green FFT
Tartan green FFT1008×672 56.9 KB

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That’s because instead of taking a screenshot, they took a photo of the computer monitor.

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Very good point! Deleted my comment re: oversharpening.

Not often one sees an actual shot of a screen presented as an example of something …

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Thanks Todd. Unintentional!

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Hey its easy to click…the other one I have seen like this is people turn on the focus mask and wonder what is up…