In a message dated 2/24/2003 10:29:55 PM US Mountain Standard Time, pcjones@attbi.com writes:
Emmanuele,
I recently went on a mount evaluation quest in an effort to purchase what I
hope to be a supreme astrophotography mount. The price, features, and goto
functionality of the new CGE, along with my happy experience with its
predecessor--the CI-700--had me interested. I had hoped Celestron would
improve the polar alignment scope since the CI-700 version is lame. So what
did Celestron do about it? There is no polar alignment scope for the CGE.
OK so you sight along the polar axis and guestamate where Polaris ought to be then you point your scope to a star due south 20 degrees or so above the celestial equator and note the star drift and correct for azimuth. Then find a star due east of your present star then note the drift and correct the mounts altitude this is known as a star drift alignment. You can then Sync computer on a known star and not only will your mount be polar aligned but the goto will be up and running as well.
You can also align on Polaris using the 2 star method outlined in the yet to be published manual then do your drift alignment of course then you have to resync on a new star. At anyrate your going to do a drift alignment to get your mount perfectly polar aligned in the first place! A polar alignment scope only gets you in the ball park. You still have to drift align the mount.
How do I know this! I own an AP 900 goto mount. Yes, I use a polar alignment scope however I've aligned using the goto feature and I've aligned using the sight long the polar axis trick. I even have daytime polar aligned my mount and found Jupiter and Saturn the Moon Regulus and Sirius in the daytime. Setting up the mount cold turkey using a small carpenters bubble level and a magnetic compass to initially align the mount.
In all case's I resort to drift alignment manually then I resync on a star. My typical Routine is polar scope the mount. Then go right into a manual drift alignment then after that is accomplished I sync on a known star. I seldom use the two star or one star and Polaris in the goto computer anymore. If you have an ST4 you can do a manual drift alignment using that device, some say it is even faster.
In short all is not lost just because you don't have a polar scope its a nice feature but is not really needed. It would take a bit longer to do the drift alignment and that is about all.
If all your going to do is observe visually you can then use the polar alignment feature in the goto computer. However for Astro-Photography then you have to drift align.
Clear Skies
Dwight L Bogan
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