Return to the Cloudy Nights Telescope Reviews home pageAstronomics discounts for Cloudy Nights members
· Get a Cloudy Nights T-Shirt · Submit a Review / Article

Click here if you are having trouble logging into the forums

Privacy Policy | Please read our Terms of Service | Signup and Troubleshooting FAQ | Problems? PM a Red or a Green Gu… uh, User

Equipment Discussions >> Mounts

Pages: 1
Rolex2
member


Reged: 09/05/13

Losmandy GM8 problem...still new
      #6123792 - 10/07/13 11:12 PM

Set the gm8 and Gemini 2 for a great night of viewing. At some point I lose alignment. It does not matter if I align with 1 or 2 stars. Obviously I am doing something wrong. Help would appreciated. Rowland

Post Extras: Print Post   Remind Me!   Notify Moderator  
ErikB
super member


Reged: 02/05/06

Loc: Central Arizona
Re: Losmandy GM8 problem...still new [Re: Rolex2]
      #6123939 - 10/08/13 12:34 AM

I don't know if you already posted and got some advice, but starting from scratch the first possibilities that come to my mind are:
1. Your clutches aren't tight enough, and one slipped, either because you touched the scope or due to slight imbalance. Since the Gemini normally uses only encoders attached to the motors, when the clutch slips, the motor doesn't turn and the encodes doesn't change its output, so Gemini thinks there has been no movement.
2. You might have a bad contact somewhere in the Gemini or associated cables.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Hilmi
Post Laureate
*****

Reged: 03/07/10

Loc: Muscat, Sultanate of Oman
Re: Losmandy GM8 problem...still new [Re: ErikB]
      #6124070 - 10/08/13 03:02 AM

The problem is that you are aligning with only 2 stars. You need at least 3 to the east and 3 to the west. I prefer 4 on each side.

The first star you align to on each side doesn't even get added to the model, it just does an index correction. every subsequent star after that is what actually what gets built into the model.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Raginar
Postmaster
*****

Reged: 10/19/10

Loc: Rapid CIty, SD
Re: Losmandy GM8 problem...still new [Re: Hilmi]
      #6124495 - 10/08/13 10:09 AM

Checks. I'd go to the Tom Hilton website and read through all the pages.

Post Extras: Print Post   Remind Me!   Notify Moderator  
Rolex2
member


Reged: 09/05/13

Re: Losmandy GM8 problem...still new [Re: Raginar]
      #6124788 - 10/08/13 12:10 PM

What is tom's website?

Post Extras: Print Post   Remind Me!   Notify Moderator  
Raginar
Postmaster
*****

Reged: 10/19/10

Loc: Rapid CIty, SD
Re: Losmandy GM8 problem...still new [Re: Rolex2]
      #6124797 - 10/08/13 12:14 PM

www.gemini-2.com. It's a must read.

Post Extras: Print Post   Remind Me!   Notify Moderator  
tomcody
Carpal Tunnel
*****

Reged: 07/06/08

Loc: Titusville, Florida
Re: Losmandy GM8 problem...still new [Re: ErikB]
      #6125120 - 10/08/13 02:41 PM

Quote:

I don't know if you already posted and got some advice, but starting from scratch the first possibilities that come to my mind are:
1. Your clutches aren't tight enough, and one slipped, either because you touched the scope or due to slight imbalance. Since the Gemini normally uses only encoders attached to the motors, when the clutch slips, the motor doesn't turn and the encodes doesn't change its output, so Gemini thinks there has been no movement.



Rolex2,
You did not say how much you loose alignment? like just to the edge of the field of view or way off position?
But Eric's advice about the clutch slipping is the first place to check. One thing to remember is that the original Losmandy design called for digital drive and the ability to push the scope to the next target, so the clutches are designed to slip to allow you to push it around. Now along came the Gemini Goto and the clutch slipping was a bad thing as in, it slips and you loose position, not what you want with computer control, so what did Losmandy do? come up with the clutch knobs with three handles or levers on them so you can"really tighten that clutch up" . and no more slipping. Now you do not necessarily need the three handle knobs, but you now know why they are made , and maybe that is what is causing your problem?
Rex


Post Extras: Print Post   Remind Me!   Notify Moderator  
RAKing
Postmaster
*****

Reged: 12/28/07

Loc: West of the D.C. Nebula
Re: Losmandy GM8 problem...still new [Re: Rolex2]
      #6125313 - 10/08/13 04:07 PM

Sorry to hear about this. I use my GM-8/Gemini with nothing more than polar alignment and one star. Maybe more stars are better, but I have never had any issues with one.

I also think a slipping clutch might be the culprit and hope it's nothing more serious. (I use the three-prong clutch knobs, too.)

BTW - I also added DSCs to my GM-8 this year because the last time I used this mount at a public outreach session, someone grabbed the eyepiece just a bit too hard and knocked everything out of alignment. With the DSCs connected, my Gemini can always find its way back home.

Cheers,

Ron


Post Extras: Print Post   Remind Me!   Notify Moderator  
Raginar
Postmaster
*****

Reged: 10/19/10

Loc: Rapid CIty, SD
Re: Losmandy GM8 problem...still new [Re: RAKing]
      #6125352 - 10/08/13 04:17 PM

I wish the DSC worked with my Gemini-2...

Post Extras: Print Post   Remind Me!   Notify Moderator  
tomcody
Carpal Tunnel
*****

Reged: 07/06/08

Loc: Titusville, Florida
Re: Losmandy GM8 problem...still new [Re: Raginar]
      #6125508 - 10/08/13 05:38 PM

Quote:

I wish the DSC worked with my Gemini-2...



there is a thread about that, the new high resolution Losmandy kits should be ready in a couple weeks, then Rene may activate that function in the Gemini II.
Rex


Post Extras: Print Post   Remind Me!   Notify Moderator  
RAKing
Postmaster
*****

Reged: 12/28/07

Loc: West of the D.C. Nebula
Re: Losmandy GM8 problem...still new [Re: tomcody]
      #6125530 - 10/08/13 05:48 PM

Quote:

Quote:

I wish the DSC worked with my Gemini-2...



there is a thread about that, the new high resolution Losmandy kits should be ready in a couple weeks, then Rene may activate that function in the Gemini II.
Rex




Sorry, I thought it was active. My fault for mentioning it.

Ron


Post Extras: Print Post   Remind Me!   Notify Moderator  
tomcody
Carpal Tunnel
*****

Reged: 07/06/08

Loc: Titusville, Florida
Re: Losmandy GM8 problem...still [Re: RAKing]
      #6125887 - 10/08/13 09:24 PM

No problem,
If I remember its in this mount section and called Losmandy DSC's?
I spoke with Scott and the new encoder kits may be ready in mid October.
Hopefully, then Rene will activate the encoder suppport in Gemini II's.
Rex


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1


Extra information
9 registered and 27 anonymous users are browsing this forum.

Moderator:  Dave M, richard7, bilgebay 

Print Thread

Forum Permissions
      You cannot start new topics
      You cannot reply to topics
      HTML is disabled
      UBBCode is enabled


Thread views: 380

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics