Since getting the dome I had never been able to get the dome and scope to align for full sky. There was either guidescope overlap or main ota overlap.
I went back to basics, checked all the posts on here, re-read my understanding and then got the tap measure out (again!).
Checked where the dome centre was relative to my mark on the floor.
Checked all the wall posts were equidistant from the mark (all approx 44")
Checked the east/west, north/south and gem offsets.
And this is where it struck me I had made 2 key mistakes;
1) I had used the tripod centre and not the RA/DEC axis crossing
2) I had not factored in the guidescope as part of the optics for the GEM distance
Having adjusted the numbers.......it sync'd in all directions for the first time ever and I became a very very happy bunny!
Here is a video on the above.
Clear Skies!
Dave
Dave great video, good info! I'm just putting my dome into service and am having to deal with all these issues now. Just curious, what was your final telescope offset value including factoring in the distance of the guide scope. I also have a RASA 11".
I'm curious how you deal with the issue of taking flats as well.
Bill Gwynne
aka "Bill the Sky Guy"
Thanks for sharing. I've done what you have done, then realized the same thing about the RA/DEC center of rotation. Unfortunately when I remeasured the dome to scope the sync got worse. I will however, remeasure to the dome center from each post. I have been measuring only from the cardinal points.
Steven