You need to make sure your phone is very still before it appears. I usually will lay mine on a table or the top of a car and then tilt my head underneath it until it appears and when it does gently hit the button. I’ve gotten some pretty cool results from it like shooting stars and even the Milky Way.
This looks super interesting! I’ve been looking for a simple “cyberdeck” build for awhile now. I think this one might be it. It looks like there’s quite a bit of room in the chassis, I wonder if you can fit a full Raspberry Pi in there with minimal tweaking.