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Humayan,
Can I just confirm a few things to understand if there are any unexpected side effects.
On my Skysensor2000-PC - I set up a 3 star alignment and enter the permanently set up mount into polar aligned mode. I believe I'm well within an half arc minute of the SCP, so the SS2K compensates for DEC drift periodically quite well. I believe the SS2K loses about a second a day, so I reset its clock at the start of each session. I also check the 3 star alignment every quarter or so.
Each quarter - after I have my 3 star alignment for the mount's hand controller I build an 80 star sky model in Maxpoint. Mmaxpoint confirms I am about 20 to 40 arc seconds off the SCP and generally improves my pointing from abour 3 arc minutes to say 55 arc seconds.
So generally each night I image in a quarter I just check the focus is correct with a Bhatinov mask - then get straight into framing my first target. Let's say its M20 - I goto to it and calibrate my autoguider - PHD - usally on 3 second intervals. Then I switch off the guiding and just leave it in passive mode until I have M20 framed exactly where I want it in say 60 - 120 second test shots. This is trial and error a bit and might take me around 5 - 10 minutes to do satisfactorily!
From there I switch the autoguider on, let it stabilise for a minute then leap into imaging runs over a course of nights.
PS My arc seconds per pixel is 0.44.
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With your method - I'd do the same - up to the slew to M20, in say the Sky6, but then I take shots using MaximDL (rather than DSLR Shutter -> DSUB -> Canon EOS Utilities) so that it rather than Canon's Zoombrowser gets the image. Next under MaximDL I'd plate sove - to get exact coordinates and issue a sync. I presume the sync only updates Maxpoint or does it change the SS2K controller too?
Qu 1. What does the sync do to both MaxPoint and SS2K's sky models? Do I have to worry that this will stuff things up (i.e. like change one of the SS2K's 3 alignment stars and reset its drift compensation algorithm's incomprehensible parameters incorrectly or wierdly)? Or does the sync only adjust MaxPoint's pointing parameters and leave teh SS2K sky models calibration stars unaffected. I remember playing with sync once under CDC or maybe the Sky6 on a nebulae and had pretty wierd pointing behavour until I relaised the mount's 3 star model was confused!
So I solve the current test shot and sync - then I reload night one's correctly framed image and solve it and issue a goto to it to eliminate the discrepancy - which sounds really clever. Any residual pointing error should only be a backlash factor - so very small indeed.
Many thanks if I have understood this correctly.
Matt
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