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ASIAir vs. Polemaster for PA

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#1 silverking


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Posted 26 March 2021 - 11:18 PM

I've owned a Polemaster for quite a while now, and recently purchased an ASIAir Pro for the advanced imaging features.

Having the AAP already hooked up, I began using its PA routine rather than bring out my laptop in order to use the Polemaster.

I could never quite get the AAP routine to give me a "dead on" reading, and in fact many of the adjustments I was making while watching the AAP app screen simply weren't making any sense in terms of directional travel, with a continued adjustment in exactly the same direction as the previous adjustment suddenly making the target dash to the other side of the adjustment point on the tablet screen.


So I thought I'd try a direct comparison, at exactly the same time ... of the PA routines between the AAP and the Polemaster.


I set up the Polemaster and got it dead on ... green box over top of rotating circle, something I've done hundreds of times before.

I then disconnected the Polemaster laptop, and ran the PA routine in the AAP ... only to find that the perfectly aligned mount as per the Polemaster PA routine was now reading anything but perfectly aligned on the AAP PA routine.


Based on my guiding graph, the Polemaster routine is the accurate alignment ... and the AAP routine is less accurate, with many more guiding corrections required after doing the AAP PA routine.


Perhaps it's the difference between a plate solve with the camera directly on the RA axis (Polemaster) and a plate solve with the camera actually rotating freely in space (the AAP main camera on your scope).

I'll have to do some more testing, but I don't believe that the AAP PA routine is as accurate as the Polemaster PA routine ... and my guiding graph backs that notion up.

#2 Oyaji


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Posted 27 March 2021 - 01:49 AM

I'd like to see a head to head compro:


Polemaster PA with PHD2 Guiding

Polemaster PA with ASI guiding

ASI PA with PHD2 guiding

ASI PA with ASI guiding.  


Easier said than done, of course--but enquiring minds want to know!  

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#3 lightpolluted


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Posted 12 June 2021 - 03:30 PM

Silver king - I’m curious if you’ve had any additional conclusions since your post.  I recently purchased a Polemaster and was able to get it running and aligned very quickly with my AVX.  I then started looking to buy WiFi adapter for AVX and learned more about the ASI Air Pro and whether I could replace Polemaster, a Celestron WiFi module, and PHD for guiding (and sell pole master - effectively paying for the ASI Air, and getting 3 functions…..but before doing so was looking for some experience from Cloudy nights folks.

#4 michael8554



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Posted 13 June 2021 - 03:38 AM

I'd be more interested in a Polemaster PA - followed by another Polemaster PA.


Same reading ?


Repeat for the other systems.


PA errors are tiny and very hard to measure accurately, so repeatable and comparable results may be impossible.


Stick with the one that gives the best encore, or is quickest to use, because a PA error of 5 arcmins is easily guided out.

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