My understanding is that it takes into account air's refraction effects when processing both tracking and pointing.
Dual chip - agreed would skirt these problems
Simple tracking adjustment - if its a rock solid constant delta - actually yes it will (but I'd like to know why its a constant delta!) It seems irreconcible to me that pointing is really excellent (I've had it down to 34 arc seconds) when tracking is out - they are heavily related so should be directly affecting each other.
A model of 360 motion would be brilliant and yes if you had it and tracking rates were consistent - you could easily apply this tracking correction periodically. In fact this is basically what Tpoint and ProTrack do for the PME and what MaxPoint and Smart Track try to do for any other ASCOM controlled mounts!
It's simple once you have the data - a 2 dimensional matrix of correction values you simply look up by (Alt, Az) to apply a RA correction - possibly smoothed by a fitted curve to the nearest sample points. You could build the matrix by slewing, and observing, - which is just one step more complicated then Tpoint or MaxPoint already do to capture pointing correction data). Then you simply read the matrix every 15 minutes based on pointing paramaters to find the best fit / smallest pulse guide correction pulses to add to the mounts movements. Smart Track does this - its just not yet as good as I'd like!
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http://winfij.homeip.net/maximdl/smarttrack.html
SmartTrack MaxPoint addon
This addon application for MaxPoint uses the pointing model generated for your mount to enhance its tracking accuracy as well as its pointing accuracy, allowing longer unguided exposures to be achieved, useful for imaging in the field where setting up an extra guide scope is troublesome.
SmartTrack will automatically compensate for all of the error parameters modeled by MaxPoint, including polar misalignment, RA/Dec bias, axes misalignment and tube/mount flexure. It will also correct for the changing atmospheric refraction if you have enabled that in MaxPoint.
It does this by constantly monitoring the difference between the physical coordinates of the mount and the corrected coordinates those physical coordinates would map to once the mount model correction has been applied.
If the difference goes over the specified allowable error, ASCOM pulseguide() commands are sent to the mount to correct it’s pointing.
An example of the level of correction achievable is shown below. This is an animation of a pair of 400 second (6.7 minute) test shots through my 10" LX200R SCT, one regular unguided shot, the other also unguided but using SmartTrack.
The scope has a focal length of 2760mm, giving an image scale of 0.67 arcsec/pixel. The trailing is evident in the unguided image, but greatly reduced by running SmartTrack.
