That's the idle temp? Seems high. I idle at 41c and it took pegging the 4 cores at 100% for ten minutes to get to 56c

I can't recommend this case enough. It's made by one dude in California who quit his job to just machine these cases.

I see from the screenshot memory utilisation at 22.6% or 884.2 MiB.
Is this what KStars and INDI use?
Would a 2GB Pi4 be enough?

I would personally recommend 4Gb if you can get it. It will help with handling incoming images/FITS files. Avoid the use of a swap partition if you can as it is hard on SD cards. With only 2 GB ZRam could be implemented to make up a shortfall.

I agree with lhoujin. My experience with Ekos over the past 2 years is “the more memory, the better”.


Wouter

All of my pis have zram enabled, no matter which os they are running. My pi 4 is 4gb and has zram enabled giving it close to 8gb ram effectively

I have an 8MP mono CCD camera and 1GB without zram is good enough for Ekos + PHD as long as I don't run Chrome browser. With my PI4 which has 2GB RAM and no zram, I have plenty of memory. Make sure that you enable System monitor on Mate panel which shows both CPU and memory so you can monitor memory closely. Keep in mind that Linux reports memory usage in a very confusing fashion - it considers buffers and caches as non-free memory even though it can be used if the system runs out of memory. In Mate panel buffers and caches are shown as light green.

I'm seeing 104F/40C with the fan blowing in (out, I get about 8 degrees warmer). I haven't patched the new firmware yet.

Hmmm, the case fan should be pulling the air into the case through the heatsink and out, so the fan should blow out of the case... well mine does anyway and does not go above 52 degrees...

Yeah, I've heard that. I tried both ways and tested the temperatures and I get about 8 degrees cooler with the fan blowing in. Now I do keep my house at 72 degrees with the air conditioning, but the test was done with the same room temps.

Would not blowing in be more likely to bring in dust/debris? Of course air still comes in to replace the outgoing air in that configuration, but it is lower velocity.

There are no moving parts in the Pi so it wouldn't affect it. Noncunductive dust here and there isn't going to short anything.

Thats a good point, but it wouldn't help the thermal issues. What do you think about dew? I'm not sure if it would make a difference for that one.