I haven’t been clear on how the rotator angle is being set and what it means.
I am using OAG and I want the rotator angle to indicate the exact angle of the OAG - independent of the image angle. So I can manually adjust its angle so it is exactly N/S and at that point use Manual Sync to set the value to be exactly zero - and I hope stay that way - assuming that calibration is stored with the Pyxis 2" rotator. I’m hoping that calibration ‘sticks’ and is the same after I shut down and start a new session.
From then on I want the angle in the rotator control to correspond to the true, calibrated OAG angle - independent of the image angle.
But I’m seeing odd numbers showing up in the fits header and in the rotator control. RIght now the Position value in the rotator control is 123.66 after I had done a Set Position of 124.0. That by itself is ok and it means I asked for 124.0 (oag angle) and got 123.66.
But the FITS header says the Image Angle is 123.66 and the camera rotator position angle is 126.27 - this is in an image captured during a sequence. The difference of about 3 degrees is about how far off the oag angle is from being calibrated to N/S.
I can provide logs - but this is largely a question of what these numbers mean and what sync does. I want to calibrate the rotator based on my own definition of what zero is - and from then on have that number stored in the fits header as the rotator angle. This lets me dial in oag angles accurately - and it lets me take flats at the exact angle the image was taken - all referenced by the OAG angle.
So what does sync do exactly - and how are the angles in the fits related to the values in the rotator control? Do the numbers get changed after doing a solve and sync? If so I wouldn’t want that to affect the rotator angle. It’s ok if it sets the Image Angle based on the plate solve - but I want the rotator angle to be set by the sync I did and nothing else.
Thanks,
Frank