Quote:
Originally Posted by chiaroscuro
My next step is to learn how to drift align, now that I've got a reticle eyepiece.
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Luke, forget about drift aligning a SynScan EQ mount, it's a waste of time (except of course for the CCD based variant, which is fast and accurate).
I get sub-arcminute polar alignment with little effort and the help of SynScan v3.35. With some input from forum mates (esp Wavy) and recent practice I think I have it down pat now. Here's what I do:
The altitude adjustment is straightforward, the elevation scale on the mount and/or a clinometer on the counterweight shaft gets you close enough for the software to finish it off. For azimuth, the trick is to find south, of course. With cars, mounts, steel tripods etc around magnetic compasses have a hard time making up their mind.
Starting with the mount in "home position" (counterweight shaft at its lowest position, OTA parallel to RA axis) I simply guess the south direction and start a 1-star alignment. The RDF or finder scope will miss the alignment star by some amount, depending on how well I guessed south. I then yank the tripod around to get the scope pointing as close to the alignment star as I can. This will reduce the gross azimuth alignment error.
Next, I run a 2-star alignment to its completion, after which the hand controller will display the alt and az alignment errors. If the az error is less than a degree I move on to the SynScan polar alignment routine. Otherwise I yank the tripod some more and run another 2-star alignment.
From this it takes me two or three runs of the polar alignment routine, followed by a 2-star alignment each time, to get the polar alignment error to under 1 arc minute in both directions. This is much better than I need for visual, but I do it anyway because it's fast and easy to do (provided I can see alignment stars).
For AP you may want to follow up with CCD drift alignment, depending on your planned exposure times.
Drift aligning by looking through a reticle eyepiece takes forever in comparison, is a waiting game and can be a bit of a mind twister.
That said, you will definitely need to use that reticle eyepiece for star and polar alignment. Guessing will only cause frustration.
Cheers
Steffen.