Yes, you can re-calibrate just the lens shading tables in the camera tuning file. To do this:
1. Check out chapter 6 of the Camera Algorithm and Tuning Guide.
2. However, you won't need the colour checker chart because you won't need the colour calibration images. But it will be useful to have some kind of flat field target (such as an LED video lamp).
3. Capture only the "alsc" calibration images as described.
4. Instead of running the full tuning tool ("ctt.py"), run "alsc_only.py" instead, like so (replace "pisp" by "vc4" for non-Pi 5s):5. Finally replace the "rpi.alsc" parameter block in the current camera tuning file by the equivalent block in (from the example) alsc.json.
Unfortunately the aforementioned guide doesn't contain this information, but I will endeavour to get it updated.
1. Check out chapter 6 of the Camera Algorithm and Tuning Guide.
2. However, you won't need the colour checker chart because you won't need the colour calibration images. But it will be useful to have some kind of flat field target (such as an LED video lamp).
3. Capture only the "alsc" calibration images as described.
4. Instead of running the full tuning tool ("ctt.py"), run "alsc_only.py" instead, like so (replace "pisp" by "vc4" for non-Pi 5s):
Code:
./alsc_only.py -t pisp -i /path/to/alsc-images -o alsc.jsonUnfortunately the aforementioned guide doesn't contain this information, but I will endeavour to get it updated.
Statistics: Posted by therealdavidp — Tue Dec 16, 2025 2:46 pm