Assessing Tilt: How to properly orient what ASTAP displays to which side of camera?
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Han, I have purchased and installed a Baader tilt adjuster (three screws) next to my ASI2600MC-P in my imaging train. How do I visually orient the tilt octagon I see in ASTAP with how I look at the camera from the rear of my rig (looking at my camera from the non-scope side)? ASTAP always tells me I need to flip the image (is that switching top for bottom?)
Bob
The octagon is more sensitive then the triangle so I would use that. You can flip the view vertical and horizontal under menu View. It probably helps to solve an image first and then set flipping such that north is up and east is left assuming you live in the northern hemisphere. But you have to empirical find out what each of the three screws is doing to your tilt.
In tab monitoring you could setup ASTAP to display any new image created solved and tilt measured.
Cheers, Han
Do my four steps and assumptions (below) seem correct? My Step 4 shows my assumptions regarding orientation of my camera as I am viewing it while standing behind the telescope and camera.
Thank you so much,
Bob
Last edit: Bob Kidd 2025-04-13
Hi Bob,
You have imaged M51. That is relative close to the celestial pole. I think it is easier if you look to the south or alternative east or west. Secondly your camera is rotated 96.6 degrees relative the north. I think it is easier if the arrow indicates about 0 or 180 degrees.
So I would point the telescope to the south and then rotate the camera till it is horizontal and the indicator in ASTAP is indicating about 0 or 180 degrees after solving and the north-east pointer pointer is pointing either up or down.
Else you could also start to turn the screws one by one by one but that it a little more difficult then when you would point the telescope to the south.
Your tilt is very minor. Once it is reasonable good leave it. Getting perfect could be too much hassle and next day it could different because things are bending depending on the orientation of the telescope. Or there one side of the optics is a little imperfect giving the impression it is tilt but it isn't. For your image for example the left bottom the values are a little higher but the right top not. That could indicate a minor optical problem rather then tilt. The measurement is very sensitive. So once it is reasonable symmetrical start imaging and enjoy the clear sky.
Cheers, Han