That is why I built DIY microscope with ~40€ chinese C-Mount long-working-distance optic & "Allied Vision" industrial GigE camera.
What you see is about working distance. Yes, it is enough to do hot air without angled nozzle.
9V battery for scale. GigE does a fine job of 30FPS low latency video to the PC. Magnification is partially set by size of computer monitor
Allied Vision "Demonstration Software" is avaivable from Win x86 to Linux arm_v8 64bit. I tried running it on orangepi - just fine.
Only downside is said cameras are only avaivable sporadic on ebay for ~100€ for 1280x1024. But they are very light sensitive.