I haven't had the chance to have a long go with the ASI1600 yet, I got bogged down trying to find a solution for the toupcam. Hope you find a way to get the latest kernal. I thought of trying to build one from source but it's beyond my Linux skills at the moment.
RPi4 4GB mem running Raspbian (PiOS), Indi/Kstars
Skywatcher AZ-EQ6, Esprit 100ED, Celestron HD925, ZWO1600MM, ZWO EFW,
I'm also having a look at the Odroid N2+ 4GB. It's even faster than the Rock Pi, and has active development. They have 5.11 kernel with Ubuntu 20.10 and Debian 11 running on it. And it has a 40-pin GPIO header compatible with my stepper motor HAT.
I'm amassing quite the collection of single board computers.
So thanks for the heads up on running Armbian. It works much better. I've been running KStars just looping exposures on both my imaging camera (ASI1600MM Pro) and guide camera (ASI290MM Mini) continuously for about an hour, with no hiccups. Sweet!
I need to rewrite my stepper motor INDI driver once again, because Armbian uses a different method for accessing the GPIO pins. But I'm getting good at porting this to new OSes.
One thing somewhat concerning, is that when I plug my powered USB3 hub into the upper USB3 port on the Rock Pi, I get nothing. lsusb doesn't show anything, other than the built-in hubs. Plugging into the bottom USB3 port works fine. Dead USB3 port? It doesn't affect me, because everything goes over the powered USB hub. But weird just the same.
Last night was a full night of imaging with the Rock Pi 4B. ASI1600MM Pro imaging camera, and ASI290MM Mini guide camera. No issues. I also had my Waveshare Stepper Motor HAT installed on the board. Autofocus worked beautifully as well. As a bonus, the HAT provides power to the Rock Pi, so I didn't need a separate 5V supply for the Pi. Just the 12V that goes to the HAT, and it provides 5V to the computer via the 40-pin header.
I do like the extra speediness of the Rock Pi. Especially the storage. I used a 16GB eMMC module, got it as a kit. So much faster than the SD card on the Raspberry Pi. Even the built-in WiFi works better than the Raspberry Pi.
So I would definitely recommend this as a pretty much drop-in replacement for the Raspberry Pi for most people. The only thing that would slow down most people is having to build INDI and KStars from source, since there aren't any repositories for that yet. And Astroberry wouldn't work. So there's some manual work to do, which may not be for everyone.
One nice thing about the Odroid N2+ that I was considering, is that it takes 12V input, and not 5V. So for people like me that have a 12V distribution block (Rig Runner), that makes things simple. I will probably pick up an Odroid N2+ 4GB, just to play with. The specs are even better than the Rock Pi, and is still compatible with my stepper motor HAT.
When comparing your RockPi 4b with the RPi4, I've read that you say it's much faster. Are you comparing with an RPi4 with SSD? For sure the SSD improves the speed of the RPi4 too (e.g. I'm currently running an 8Gb Rpi4 w/SSD).
Also, it seems many computer boards are hard-to-get these days. E.g. I've been looking into the latest NUCs, and they're always out-of-stock. Have you tried any of those?
Sorry, yes I was comparing Rock Pi with eMMC to a Raspberry Pi with SD card. So probably not a fair comparison. But the Rock Pi does have a faster CPU than the Raspberry Pi. And for me at least, the WiFi on the Rock Pi gets a stronger signal, and therefore faster speeds than the Raspberry Pi. I haven't needed to use my USB WiFi dongle with the Rock Pi.