I've been wrestling this more and there is indeed a memory leak. I don't yet know how or why, but it doesn't happen always but most of the time on my tests.

Happened after the last episode:
1. I installed a fresh Raspbian Buster and manually installed indi-full using the official repository
2. I ran the first tests and found out that it was working properly. I ran a few test runs with 100 frames and it worked just fine for at least three times. Also my FITS frames were now working (at least a few times when I tested). The memory consumption stayed near 60M.
3. Took the whole setup outdoors and controlled it from indoors. Same hardware, same network, same everything. The only thing changing was that I took the tracker outdoors. So a bit worse network and quite a bit colder. This time it always crashed after the Raspberry memory was full. Tried restarting everything a couple of times but no luck.
4. Back indoors a few days later: tested a few runs by restarting things and trying again. A few times everything just worked.
5. Next session outdoors and nothing works. Even tried changing the Raspberry power to a more powerful 3A one. No changes, reserves memory until the driver gets killed by OOM killer.
6. Got annoyed and pulled a huge USB-cable from the carage outdoors and connected everything with wires. No Raspberry in between. This time I managed to get around 400 frames during the night with a single sequence. BUT: when I checked the computer after the sequence, the driver was reserving over 4G of memory. It just didn't crash because my 16G RAM was enough for it. So it was evident that it's leaking memory also on Ubuntu laptop. I posted a screenshot of that.

I still have no idea what is causing the crashes or the randomness with memory leaks. If I can share some logs or something, please tell. I can try another Canon EOS a bit later when I get one on my hands.

Also about the FITS frames: for some reason I usually only get some random grayness on the FITS frames I take. It looks like a bug as well and it's really annoying since it prevents me from using all the flashy tools in KStars.

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