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How to change the star used for alignment fine tuning?

QHYCCD QHY PoleMaster QHYCCD PoleMaster Polar Alignment
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Scott Stirling avatar
Scott Stirling avatar
At the end of the PoleMaster alignment routine there’s a fine tuning stage where you hit a button to start monitoring and then fine tune alignment via the green and red (pole and axis) symbols.

Is there any way to change or control which reference star PoleMaster selects for monitoring?  For me it always selects a star that is diffracted by a tree branch.

thank you,
Scott S
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Aaron Hakala avatar
Aaron Hakala avatar
Scott, polemaster is monitoring Polaris. You can’t change it as far as know. I actually turn it off once I am aligned. Monitoring it won’t help it if something changes.  I just run with it.
Scott Stirling avatar
Scott Stirling avatar
The alignment refinement with the “Start Monitoring” button monitors two reference stars, A and B: Polaris (in the northern hemisphere) is one and the second reference star, not Polaris, is selected by the application and that is what I want to control.
Aaron Hakala avatar
Aaron Hakala avatar
Hmm, do you mean the red and green circles that appear when you hit start monitoring?  If so, those are not stars but the position of axis of rotation (as measured by polemaster) not actual stars. You need to align them with your altitude and azimuth. that is the precise adjustment.  
If you are going through the routine and matching the stars in the overlay and make it as far as moving Polaris into the green circle. You should be ok. Your fine adjustment “start monitor” is just showing you the measured axis of rotation. You need to align them and that’s it.  
If your having trouble with getting the stars to line up with the overlay because of a tree that could be a problem.  You don’t have the option of picking different stars as far as I know.
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Scott Stirling avatar
Scott Stirling avatar
I feel like I’m having a conversation with ChatGPT.  Have you ever used a PoleMaster?

One idea I have yet to try out is rotating the PoleMaster a good 180° or so and run through the routine and see if it will select a different reference star for the fine tuning monitoring alignment based on a different camera orientation.
Arnie avatar
Arnie avatar
You would probably get more help if you were a little more polite. I have been using PoleMaster for almost 20 years and it is exactly as Aaron said; there are no stars used during the fine alignment monitoring at the end of the process to get "diffracted".

Maybe rotating the camera will work for you, maybe not. But if you read the directions they say the camera should be aligned with its USB port to the left as one looks at it from the front of the scope.

Good luck,

Arnie
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Eddie Bagwell avatar
Eddie Bagwell avatar
I have been using the PoleMaster for 2 years and I'm in agreement with Arnie. You choose a reference star to start, then rotate the mount twice, then back to home, then adjust the mount to center at Polaris. Lastly, after selecting the "Start Monitor" button, you are just lining up the red and green symbols to fine tune the alignment. If you have a clear view of Polaris and one reference star you should be good to use the program. I also have a problem with trees in the PoleMaster FOV but always use a reference star that is viewable. Not sure if rotating the camera will work or make a difference as I always have it in the same position with the USB connector at 3 o'clock from the front of the mount.

Good Luck
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Monty Chandler avatar
Monty Chandler avatar
Sounds like you need to trim a branch.  You don't select stars in the polemaster.  But it works better than anything for precise polar alignment.  Both of my eq6r's have one.  You don't rotate the camera.  It actually needs to be mounted as instructed.  Spot on polar alignment every time is the result.  Best approach is to put the tripod legs on the same three dots every night.  Polar alignment takes a couple of minutes,  Best of luck!
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Scott Stirling avatar
Scott Stirling avatar
I did try rotating the PoleMaster last night.  I rotated it 180 deg so the USB port was on the opposite side of the mount from where it had been.  Rotating the PoleMaster camera orientation made no difference in its reference star selection during the alignment fine tuning.

Since the axis rotation reference star *is* user defined for the PoleMaster alignment routine, it would seem logical that the fine tuning alignment routine would also allow a user defined reference star.  But I can see why it may not -- due to the f/ratio of the PoleMaster camera, for fine tuning they fixed the routine on one  relatively bright star near Polaris.  If that star is obstructed, you will not be able to fine tune the alignment because there is not any way to define an alternate reference star for the fine tuning routine.

Note, I did finally find a Google result that fit the problem discussed here:
https://www.cloudynights.com/topic/758604-polemaster-and-a-tree-near-polaris-what-to-do/

That forum user observed that the same star (Delta Ursae Minoris) is always used in the precise polar alignment routine with Polaris and PoleMaster.  The answers are -- no, no way to change it in PoleMaster, but try SharpCap's plate solving as an alternative to climbing and trimming trees or moving the mount to get that precise alignment star unobstructed.

best,
Scott S
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Scott Stirling avatar
Scott Stirling avatar
Update:  PoleMaster works great with SharpCap Pro’s Polar Alignment tool ($18 USD).  SharpCap only runs on Windows.  I did try it last night and it detected the QHY PoleMaster camera and walked me through its alignment routine when I selected the tool from the menu.

Unlike PoleMaster’s app, SharpCap automatically detects 10+ stars within a few degrees  around Polaris to plate solve and guide your alignment fine tuning.  You are asked to setup the camera gain and exposure time for the app to detect 10 or more stars with good signal strength, then rotate the mount in RA about 90° and then adjust the mount’s alignment.
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