Stack the Stars

Hello, friends of the dark. The night before last, the conditions were finally good for photographing the starry sky at night. No clouds and no moon. I actually wanted to finally test the DIY Star Tracker. Unfortunately, the tracker turned in the wrong direction. I didn't even notice this during the first test at home during the day. There's always something wrong. Obviously, the connections on the stepper motor are "wrong". The part comes from my old 3D printer. Unfortunately, I don't have a data sheet for the stepper motor. The direction can easily be reversed by making a small change to the program for the Arduino, but unfortunately not on site. I didn't have a notebook with me