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Old 13-06-2015, 07:06 PM
Cimitar (Evan)
Evan Morris

Cimitar is offline
 
Join Date: Dec 2006
Location: Gunnedah, NSW
Posts: 250
Quote:
That is correct if you have a bad alignment model or arent properly polar aligned but did a one star align ( and hence dont have a model ), or you have orthogonality errors.
...
If you have got yr RA axle very well polar aligned, doing a synch anywhere will still reset the datums in the same way, hence why you can just do a synch after drifting, vs do a full realign.
Thanks Andrew. I think I understand now. Kind of sounds like error creep... If the telescope is not very well polar aligned, then it's enough to throw the Go-To out when you move to a different part of the sky.

Quote:
Thats good, but one thing i find at times is it is difficult to get near at first, esp if the asterism at the pole isnt visible yet. In that case, you can sometimes do the polar one star first, and use the much brighter sig oct to get the wedge close "mechanically".
Then instead of drifting, just use the spin test to get the OTA parallel to the RA axle and again use the wedge controls to find/centre the asterism.
After that, again goto a bright star near the equator and synch.
Lots of ways to skin the cat.
Thanks for reminding me of this! I was out last night around 6.15pm (my usual time when I begin to setup) and I could only just make out where Sigma might be located. I then remembered that I'd usually end up working on my alignment until 9pm, only then could I start taking pictures. Very timely advice

Cheers
Evan
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