I am building a timelapse camera system with the Pi HQ Camera. At night with manual exposure settings of 20 seconds, analogue gain and digital gain settings set, during lightning storms, the image captured seems to have a horrible glow around the over-exposed area. I understand this would be overexposed, but the lines around the edge make for real issues in post production. Does anyone know if this can be fixed in post or in capture? enter image description here

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    IMHO, this is off-topic for RPi SE as it's more about digital photography than RPi or even the camera. It does appear to be over-exposed - perhaps to the point that the image data has been "washed out", and un-recoverable in post-processing. There is a Photography SE - that might be a better choice?
    – Seamus
    Jun 14, 2021 at 23:39
  • Thank you @Seamus - I'm open to feedback on this and I will try. Given this is an issue I've only experienced on my Pi HQ Camera Module and no other digital camera (of which I have shot on dozens), I feel this is a RPi issue. My suspicion is it is directly related to the Sony sensor, but unsure if this is hardware or software. Jun 15, 2021 at 1:57
  • You may be right, and I'm only registering my opinion. I'd also like to see you get a good answer, but I'm not sure your chances are the best here. I say that because I guess this will ultimately get back to your EV being "off" for some reason. Did you get any EV information with the camera?
    – Seamus
    Jun 15, 2021 at 2:36
  • I've posed on Photography SE so we will see - thanks for the suggestion. Controls are fully manual and images each image EV is based on the previous image, with coded tolerance to maintain settings for consistent (i.e. non-flickering) timelapse sequences. Here's a little example from a less lightning-loaded shoot: reddit.com/r/timelapse/comments/nwkd75/… Jun 15, 2021 at 2:51
  • Interesting footage. Do you think it could be down to the dynamic range of the sensor? It would be an interesting experiment to compare footage of the same scene shot with a decent DSLR and the Pi HQ.
    – Seamus
    Jun 15, 2021 at 3:14

1 Answer 1


Issue in this instances was with relation to the analogue and digital gains being too far apart. Changing these to be closer together seems to help the purple / blowout lines.

In follow up shoots, the bright areas are much more evenly over-exposed where you'd expect such blowouts (i.e. from bright lights in dark settings, or lightning).

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