Thank you very much David :-)
How long it took, hmm... Making the videos was around 2 hours with tinkering and focusing. Most of the time needed stacking, but since it runs automatically you can do other things in this time. Stacking time for all panels was roughly around 9 hours. The final editing took around 1 hour. So the whole time for this picture is around 12 hours. That sounds worse than it is because most of the time it takes to stack and that's automatic. I think that the time invested is around 4 hours in total.
Greetings