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Problem, G11 Gemini 2 cold start & GOTO

 

Thank you all for your past help, I¡¯m all upgraded with ver 6 and servo driver 3. I have my date, time, time zone, Lat/Lon all set correctly. I noticed that when I do a cold start in CWD pointing north with my mount angle set to the proper angle, then tell it to go to Polaris, the servos kick in and move the mount, I¡¯d assume that it shouldn¡¯t move, that it should assume that it¡¯s alreadypointing at Polaris upon cold start, am I incorrect? I then manually pointed and then pressed synchronize on Polaris, then I told it to GOTO Jupiter, after mount movement the upward angle looked roughly correct but it was pointing about 180 degrees in the wrong direction. Any thoughts? Many thanks, Bob at 7,000¡¯ in dark sky Flagstaff, AZ
 
Edited

Polaris is not exactly at the North pole (i.e., not at the CWD position) but close. What's more, the pole itself is a mathematical singularity: the RA coordinate of the pole is undefined. Stay well clear of the pole or Polaris when doing syncs or aligns because of it.
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Regards,
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? -Paul
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On Wed, Dec 11, 2024 at 01:39 PM, <bobthorpe@...> wrote:

Thank you all for your past help, I¡¯m all upgraded with ver 6 and servo driver 3. I have my date, time, time zone, Lat/Lon all set correctly. I noticed that when I do a cold start in CWD pointing north with my mount angle set to the proper angle, then tell it to go to Polaris, the servos kick in and move the mount, I¡¯d assume that it shouldn¡¯t move, that it should assume that it¡¯s alreadypointing at Polaris upon cold start, am I incorrect? I then manually pointed and then pressed synchronize on Polaris, then I told it to GOTO Jupiter, after mount movement the upward angle looked roughly correct but it was pointing about 180 degrees in the wrong direction. Any thoughts? Many thanks, Bob at 7,000¡¯ in dark sky Flagstaff, AZ
 
Edited

On Wed, Dec 11, 2024 at 10:39 AM, <bobthorpe@...> wrote:
Thank you all for your past help, I¡¯m all upgraded with ver 6 and servo driver 3. I have my date, time, time zone, Lat/Lon all set correctly. I noticed that when I do a cold start in CWD pointing north with my mount angle set to the proper angle, then tell it to go to Polaris, the servos kick in and move the mount, I¡¯d assume that it shouldn¡¯t move, that it should assume that it¡¯s already pointing at Polaris upon cold start, am I incorrect?
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No, you are not correct.??Polaris is NOT the North Celestial Pole and Gemini knows Polaris is not the North Celestial Pole.? But Gemini has a "perfect" default model and will attempt to GOTO Polaris which it likely cannot find because you have not done an accurate mechanical RA polar alignment before hand.? ? ?
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I then manually pointed and then pressed synchronize on Polaris, then I told it to GOTO Jupiter, after mount movement the upward angle looked roughly correct but it was pointing about 180 degrees in the wrong direction. Any thoughts? Many thanks, Bob at 7,000¡¯ in dark sky Flagstaff, AZ
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By doing what you are doing instead of the correct routine of mount head leveling, mechanical RA axis polar alignment using polar scope, Polemaster or other camera based PA routine, then doing at least a 2-3 star alignment AKA "model building" in Losmandy speak you are not going to have much success with GOTOs.? By randomly syncing Gemini following your routine you are setting yourself up for failure.? ?
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Start with Losmandy's basic setup videos they will help you to learn the basic setup routines to be successful with a Losmandy Gemini powered mount.?
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After you have reviewed the Losmandy videos, practiced a bunch in daylight get back to us with any questions you have.??
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--

Chip Louie Chief Daydreamer Imagination Hardware?

Astrospheric - South Pasadena, CA?
 

Thank you for your replies. So I did a test and feel better about my results. I¡¯m using a digital level to ensure that my mount is level and my angle is set to my Lat of 35.09 degrees, and a compass to ensure that I¡¯m pointing true north, a good basic mechanical alignment without a Polar scope. I did a cold start with CWD and then selected GOTO Polaris, after a RA movement of I believe 90 degrees to the left, the scope angle was close to my Lat of 35.09 degrees. I fully understand that at this step it might not point directly at Polaris but close, this is a good starting point, I¡¯m in the ballpark. Next, in a few weeks without such a bright moon, I can model / align it with west and east bright stars. Many thanks, Bob
 

Stay far away from the pole or Polaris when doing a Sync or an Align, and everything should work much better.
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On Fri, Dec 13, 2024 at 11:14 AM, <bobthorpe@...> wrote:

Thank you for your replies. So I did a test and feel better about my results. I¡¯m using a digital level to ensure that my mount is level and my angle is set to my Lat of 35.09 degrees, and a compass to ensure that I¡¯m pointing true north, a good basic mechanical alignment without a Polar scope. I did a cold start with CWD and then selected GOTO Polaris, after a RA movement of I believe 90 degrees to the left, the scope angle was close to my Lat of 35.09 degrees. I fully understand that at this step it might not point directly at Polaris but close, this is a good starting point, I¡¯m in the ballpark. Next, in a few weeks without such a bright moon, I can model / align it with west and east bright stars. Many thanks, Bob

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