Ihoujin wrote: Thank you Rob for the suggestion to use the guide camera with it's natively supported PHD2 driver. Up to now I have been using it with the INDI driver because I like being able to use it for plate solving. On the Pi3 this was practically required because it was very slow to solve a large camera image. I'm using a Pi4 now, and the plate solving performance is far better now. So I will try moving away for guide scope pointing and dedicate it to PHD2 next time.
Same here. I use my guidecam to platesolve as well. Still on RPI3B+, I will move to RPI4 asap ..
I am sorry, as the OP, that I could not comment before on all your really good suggestions and tips. I will look at all of them and try to solve this issue. Just to be clear, I run everything on the PI and only connect via VNC, I use Stellarmate, my last PA had an error of 12'' and evertthing worked fine in a previous session. so it is still hard to understand what has changed. One of my friend said that it could be because it was quite windy those 2 nights but the fact that it was an error that was predictable and repeatable rules that out... or not. I will test again a on calm night, so far I do not see what I could change or improve beside going to PHD2. Guiding used to be that least of my worries as it had always worked for me, now it is my own personal nightmare
so thanks again all for your comments and tips, I did learn some tricks and concepts better from all this !