Heq5 pro synscan alignment stars choice.
Posted 17 July 2009 - 05:22 AM
Posted 17 July 2009 - 10:00 AM
One really nice thing for these mounts is EQMOD, using a PC, u can use any star or dso in planetarium software to sync your mount before skewing to a new target. Gotos really accurate all night. I use cartes du ciel right now.
Posted 17 July 2009 - 10:57 AM
I managed to save this from a previous post somewhere on the CN forum, it seems to work well for me:
"By the way, here's a little trick someone on CN shared a while back for establishing the mount's "home position" accurately - though as I said in the preceding post, it only helps for finding that first alignment star, or if you're not doing a star alignment at all:
1. Rotate the RA axis of the mount until the counterweight bar is parallel to the ground. Use your level to verify, and set the RA setting circle to 6 hours.
2. Rotate the DEC axis of the mount until the telescope is parallel to the ground. Use your level to verify, and set the DEC setting circle to zero.
3. Rotate the RA axis until the counterweight bar is pointing down to the ground and the RA setting circle is at either 0 or 12, depending on which side of the RA setting circle you're using.
4. Rotate the DEC axis until the telescope is pointing north and the DEC setting circle reads your latitude.
This will geive you a pretty accurate "home position", and if your polar alignment is good and your date and time are set correctly in the SynScan, your first alignment star should end up very close to the center of your filed of view."
Posted 17 July 2009 - 12:55 PM
For the Synta, some empirical experience shows that:
1. Reticle eyepiece use during alignment seems to help greatly in GOTO precision;
2. For the Synta, three star alignment is intended to reduce the effects of cone error in the mount setup. If you don't have cone error, a three star alignment will often give worse results than using less stars;
3. One can get pretty good results, if the home position was appropriate, mount level, and with a good polar alignment, with a single star alignment. Home + level + good polar means all you need is one star to fix the sky orientation. Two star adjusts for off-perfect polar. For public outreaches, I can pretty much navigate all around the sky if I'm careful on the setup and not rushed for the polar and home, and only need a 1 star. If I'm off on polar and home, the alignments become awful as well.
I won't go into the twitchy behavior on alignment star choice; almost a black art with this mount. Find a set that works each season, and live with them. But, as I said, if I do the prep right I can get away with a 1-star for most purposes.
Posted 17 July 2009 - 01:24 PM
It works well enough for me I find with the GoTo always finding stuff thats pretty close to the center of a 26mm EP which is close enough for me as a visual observer.
I also always get the mount level and get a polar alignment fix.
Posted 19 July 2009 - 02:09 PM
Posted 20 July 2009 - 06:34 AM
And astro baby: I used your Idiot's Guide to learn how to do a polar alignment. It was a big help.
Posted 21 July 2009 - 06:21 PM
Posted 23 July 2009 - 06:06 AM