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Can I fix the purple lines in this image in capture processing on my Pi HQ Camera?

When shooting long exposures at night, my Pi HQ Camera has purple line artefacts where the lightning strikes, or there is extreme over exposure. This is not something I can avoid, as I do not know if there is lightning and ideally, the sensor processing would better handle this. The sensor in question is a Sony IMX477 sensor and the software controls for night exposures are manual shutter speed, digital and analogue gain settings.

For reference, please see the example image (of which I have many more). A one-off could be repaired without too much fuss, but having dozens is a pain.

purple lines in overexposed lightning areas

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  • Is this an original image? The overexposed part is far from white, the histograms of the green channel (oppoiste of purple...) doesn't reach the right side and all channels have a very sharp spike at 218. Or a defective sensor? – xenoid Jun 15 at 6:38
  • @xenoid this is an original image. The white-balance is a bit of a mess - I'm building my own timelapse system where the color temperatures (by means of blue & red gains of the sensor) are being set manually. I guess this white light from the lightning is too much for my settings. I'm honestly out of my depth with analogue and digital gains of the sensor and blue and red channels only makes my brain melt a little more. I think the sensor isn't defective - it can capture plenty nicely. I've got more info at regularsteven.com/… – Steven Wright Jun 17 at 6:06

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