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Old 16-07-2018, 09:37 PM
rally
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rally is offline
 
Join Date: Sep 2007
Location: Australia
Posts: 896
Greg,

Tpoint and the Paramount handle meridian flips really well
No need for fudging it !

You would do your normal Tpoint mapping for Polar Alignemt reporting using 6 plus stars within a few degrees of each other on the same side of meridian.
Then once you have used the Polar alignment report to adjust for a good Polar Alignment (you might do 2 quick iterations to get it down into the +/- 10 arc second range for both axiis)
Once you have a good PA on one side of Meridian, then generate a new calibration run which has about 40 mapped points on both sides of meridian and have them +80 and -80 degrees declination and some around the celestial equator.

This will produce a Tpoint model that should have you within about a stars diameter anywhere in the sky.

You need to do that as the manual states to differentiate between the different term errors that can be caused by different things - "This is so that TPoint can distinguish between the HA sync error, IH, and the OTA/declination non-perpendicularity, CH."
Doing the mapping on both sides of meridian ensure that Tpoint can correctly identify the sources of those errors and correct them.

I assume you are using TheSkyX and can so a Super Model and you are doing your Tpoint mapping using the camera rather than swapping between visual and camera

There is a good discussion of this in the Tpoint Add On manual available online.

Rally
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