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At new location mount slews to wrong locations

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#1 ssa2294


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Posted 17 September 2021 - 09:55 AM

This week was my first night imaging at my new home and I encountered a weird problem. At the start of the night I polar aligned as usual, then opened Cartes du Ciel. From N.I.N.A I had select Gulf of Mexico which by that time is around 75-80 degrees. When I issued the slew and center command from NINA the telescope did turn east, but also way way south so far that it was pointing at the ground.


So my first thought was somewhere I had wrong location/time settings. But I checked Cartes and it showed correct. Next I checked my mount's settings (GM811) and the Gemini webpage showed both time and location correct. NINA gets its location settings from Cartes, and that again showed correct. I moved back to Polaris and tried to slew from within Cartes thinking maybe it was an issue with NINA's nightly build. No dice, Cartes too also slewed to the weird location pointing to the ground (as if it was 10am and not 10pm).


The week before I moved I wasn't able to image, but did have everything setup and connected. I went through everything to make sure the first night out would be issue free, i.e. I set new location anywhere I could. I even did a test run, i.e. let NINA slew to G.o.M. and let it track for the evening. That night while I could not visibly see the target the scope did slew to a approximate location to where I would assume it needed to go (i.e. it did not slew to the carpet). 


My 2nd available night is tonight and hoping it goes problem free. Looking for any ideas on what I missed or could have done wrong. 

#2 slepage


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Posted 17 September 2021 - 10:10 AM

Losmandy mounts are prone to doing that even if you use it with just the hand controller.  When this happens, 9 times out of ten it is because your mount cables are not making good contact.  Make sure everything is nice and tight, check for any amount of corrosion and you can (if you want) use a small amount of dielectric grease to insure a good connection.  This might seem unrelated to your issue, but with Losmandy if your cables are not making good contact you will get all kinds of weird behavior.



#3 terrypaula


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Posted 17 September 2021 - 10:48 AM

I was browsing the forums and I ran into your issue and I had to respond because I had the exact same thing happen to an AVX, as a beginner.  It turned out to be a difference in epoc settings in the programs I was using to navigate.  I found all epoc settings, turned them all to J2000 and the issue never returned. 

But I'll have to be careful to watch for that as I own a GM811 with the lightweight tripod and I didn't know that Losmandy's had a this problem.  But before I turn it on I double check every connection and adjustment; reason being I'm retired and really can't afford to repair the mount. 

I've owned the GM811 for some time and it's performed flawlessly, except for gear noise when slewing really fast.


Edit point: Also I read that Losmandy mounts a similar issue but was traced to that the mount's have certain power requirements, not the usual 12volt.  The mount runs a lot better at 16volt -18volt?  I've been using the supply Losmandy sent too me.  Is there anything true about this?



Edited by terrypaula, 17 September 2021 - 10:59 AM.

#4 bobzeq25



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Posted 17 September 2021 - 10:50 AM

On iOptrons you generally want to "clear alignment data", and do a new star alignment.

#5 OldManSky


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Posted 17 September 2021 - 12:36 PM

Apart from what others have already mentioned, I would suggest one more *really careful* check on the location data entered into CdC and NINA and in the Gemini.  

Some software has you enter Longitude as positive numbers then E or W.  Some others indicate W as negative numbers, and no letter designation.

Check that whatever format your software uses, you've got that part correct.  CdC has you enter positive numbers then East or West on a dropdown, for example...

#6 Birddogoby


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Posted 17 September 2021 - 05:32 PM

I'd second OldManSky's suggestion.  I have an EQ6R mount and at the beginning of using NINA, the scope would slew to the opposite side of the meridian or some other odd place.  Drove me nuts.  I discovered the problem was the West longitude designation, which requires a "-" for west longitude with my software.

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#7 ssa2294


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Posted 17 September 2021 - 07:06 PM

Just got home and got everything connected and noticed in ASCOM device hub that my Azimuth is 180 degrees. Shouldn't that be 0? I have no idea how this happened, or where I would change any setting. Any ideas?

#8 ssa2294


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Posted 18 September 2021 - 05:10 PM

Last night I was able to somewhat successfully image (clouds did not help) and at start I found that my limits I had set were way way WAY off. So far off I did in fact crash into the tripod, though I do not believe there was damage as I was able to image for hours after. 


As far as location data, I usually just kept things the same from area I always imaged at and only adjusted the numbers (i.e. changed 42 to 45, -93 to -94, etc.). I think my issues may have been twofold, first as slepage suggested the cables may not have been firmly placed. I did insure this time around they were. Second with my limits having been way off I think it was something within the Gemini controller. I reset them and then after everything seemed normal. 


Unfortunately I did not pay attention to the limit settings before, I just set reset them without thought as I was already beaten and tired by the move. 

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