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 | 2 | (show all)
Puck Ja
scholastic sledgehammer
*****

Reged: 11/21/12

Loc: OK, USA
Atlas EQ6 kept drifting after slew new
      #6071281 - 09/09/13 12:58 PM

When I had my XT8 on Atlas (about 2 year old), onces in a while I notice that the mount kept moving after slew command. I have ensure mount was well balanced. It is visible on my imaging CCD looping at about F/3. This happened with both hand controller or EQMOD. Usually I can issue another slight "slew" to the opposite direction to stop the drifting. There may be once that the drift was bad that I have to "reboot" the mount.

Recently, I put C11 on Atlas, it was working alright for two nights. Then last night I notice quite large drift after my last slew. The PHD display of my SSAG view shows the star moving gradually out of FOV. That was significant and I just stop my session.

I have googled quite a bit but have never get firm answer on the cause and fix of this issue.

Thanks a lot for the help!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Puck Ja
scholastic sledgehammer
*****

Reged: 11/21/12

Loc: OK, USA
Re: Atlas EQ6 kept drifting after slew new [Re: Puck Ja]
      #6071959 - 09/09/13 07:35 PM

No one has experienced it? I thought that I read a lot of reports...

Post Extras: Print Post   Remind Me!   Notify Moderator  
rigel123
Postmaster
*****

Reged: 06/29/09

Loc: SW Ohio
Re: Atlas EQ6 kept drifting after slew new [Re: Puck Ja]
      #6072355 - 09/09/13 11:24 PM

A lot would depend upon your initial alignment. If your PA is off by enough you might see this. Also, just to be safe check your tracking rate to make sure it is set on Sidereal Tracking.

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


Reged: 01/23/09

Re: Atlas EQ6 kept drifting after slew new [Re: rigel123]
      #6072508 - 09/10/13 01:45 AM

Using the hand control was when I experienced such drift. When I interrupted the slew by pressing the ESC button before the mount reached its target, the RA drifted by itself. Had to reboot the mount.

Post Extras: Print Post   Remind Me!   Notify Moderator  
John Carruthers
Skiprat
*****

Reged: 02/02/07

Loc: Kent, UK
Re: Atlas EQ6 kept drifting after slew new [Re: achronut]
      #6072568 - 09/10/13 03:28 AM

First check your power supply. They need 12V 2A minimum and are happier with more, I run mine at 13.4V. All sorts of madness happens if the power drops.

What are the backlash settings on the handset? try setting them to zero and see if it still does it.

I have also heard of earth loop problems causing 'extra' slew but you'd have to diagnose and eliminate that one bit of kit at a time.
One eq6 I tuned 'drifted' simply because of bad guider calibration.


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


Reged: 05/22/09

Re: Atlas EQ6 kept drifting after slew new [Re: John Carruthers]
      #6072725 - 09/10/13 07:51 AM

My HEQ5 started to do this after several years of use. I stripped it down, cleaned the worm and gear, readjusted and the problem has gone away.

NigelM


Post Extras: Print Post   Remind Me!   Notify Moderator  
Puck Ja
scholastic sledgehammer
*****

Reged: 11/21/12

Loc: OK, USA
Re: Atlas EQ6 kept drifting after slew new [Re: NigelM]
      #6072939 - 09/10/13 10:43 AM

Thanks to all the replies. I would like to clarify my issue. It is not due to bad PA or GOTO alignment or autoguiding. The mount, when the issue occurred, will "over-shoot" after the slew command, like a heavy car cannot stop well behind the STOP sign. But once the mount stop, it will not drift and follows the autoguider well.

I suspect that this may be backlash (or any looseness in the mechanical chain), balance, and weight related. I just saw a view on Astroshed talking about balancing at different orientation. That reminds me that I may not did a good job on balancing.

Last night I switch back to Orion XT8 (lighter load to Atlas) and did not saw the large moving after slew to position.


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

Reged: 07/06/07

Re: Atlas EQ6 kept drifting after slew new [Re: Puck Ja]
      #6073445 - 09/10/13 03:38 PM

Backlash won't produce this result AFAIK. If you are currently driving on that axis, any backlash would _already be taken up, you see. Backlash would only appear when the direction of the slew was reversed. Main causes of this sort of behavior? Poor balance and computer/connection/power problems.

Post Extras: Print Post   Remind Me!   Notify Moderator  
MikeCMP
super member
*****

Reged: 07/12/11

Loc: Chardon OH
Re: Atlas EQ6 kept drifting after slew new [Re: rmollise]
      #6073633 - 09/10/13 05:45 PM

Other problem could be PAE data in the hand box adding corrections after a slew. It's aspic ally extra syncs you may have done to I prove pointing, if you have moved the mount and never cleared the sync data it could be adding an extra calibration to the end of the move.

Go into the utility menu, I think, and select PAE. I know there is a selection to clear it, and probably to view it. See if there is anything there and wipe it out.

Mike


Post Extras: Print Post   Remind Me!   Notify Moderator  
Puck Ja
scholastic sledgehammer
*****

Reged: 11/21/12

Loc: OK, USA
Re: Atlas EQ6 kept drifting after slew new [Re: MikeCMP]
      #6073754 - 09/10/13 07:11 PM

Thanks again for the input. I understand it does not sounds like backlash issue. And I have tried both HC and EQMOD, it has occured in both cases.

My feeling is that it may be due to no-well-tightened Lock lever and poor (even though good at one orientation). I'll try to balance the mount at multiple orientation to see if this issue goes away.

Thanks!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Bill W.
Carpal Tunnel
*****

Reged: 10/09/05

Loc: Western PA, USA
Re: Atlas EQ6 kept drifting after slew new [Re: Puck Ja]
      #6074294 - 09/11/13 01:32 AM

May be gear mesh. I only say that because it would take a second for the slop to be taken out. Does it track well afterwards and how is your guiding?

-Bill


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

Reged: 07/06/07

Re: Atlas EQ6 kept drifting after slew new [Re: Bill W.]
      #6074718 - 09/11/13 10:02 AM

Quote:

May be gear mesh. I only say that because it would take a second for the slop to be taken out. Does it track well afterwards and how is your guiding?

-Bill




How will gear slop make the scope continue slewing in the same direction after it is supposed to have stopped?


Post Extras: Print Post   Remind Me!   Notify Moderator  
Bill W.
Carpal Tunnel
*****

Reged: 10/09/05

Loc: Western PA, USA
Re: Atlas EQ6 kept drifting after slew new [Re: rmollise]
      #6074809 - 09/11/13 10:43 AM

Title of the post is:

>Atlas EQ6 kept drifting after slew

After. It didn't say continue.

First paragraph.

>When I had my XT8 on Atlas (about 2 year old), onces in a while I notice that the mount kept moving after slew command. >I have ensure mount was well balanced. It is visible on my imaging CCD looping at about F/3. This happened with both >hand controller or EQMOD. Usually I can issue another slight "slew" to the opposite direction to stop the drifting. >There may be once that the drift was bad that I have to "reboot" the mount.

"kept moving after slew command." I take he meant after the slew had been completed. Also, if issuing a 'slight slew' in the opposite direction stops the 'drifting' then, to me, that points to gear mesh/slop or a balance issue.

-Bill


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

Reged: 07/06/07

Re: Atlas EQ6 kept drifting after slew new [Re: Bill W.]
      #6075161 - 09/11/13 01:56 PM

"Kept" and "continue" are purty much the same thing round these here parts...

Post Extras: Print Post   Remind Me!   Notify Moderator  
Bill W.
Carpal Tunnel
*****

Reged: 10/09/05

Loc: Western PA, USA
Re: Atlas EQ6 kept drifting after slew new [Re: rmollise]
      #6075236 - 09/11/13 02:29 PM

They aren't round here...

-Bill


Post Extras: Print Post   Remind Me!   Notify Moderator  
Bill W.
Carpal Tunnel
*****

Reged: 10/09/05

Loc: Western PA, USA
Re: Atlas EQ6 kept drifting after slew new [Re: Bill W.]
      #6075302 - 09/11/13 02:49 PM

Don't forget kept drifting AFTERr slew.

-Bill


Post Extras: Print Post   Remind Me!   Notify Moderator  
MikeML
professor emeritus
*****

Reged: 10/09/04

Loc: NJ
Re: Atlas EQ6 kept drifting after slew new [Re: Bill W.]
      #6075415 - 09/11/13 03:50 PM

Couldn't be mirror flop?

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

Reged: 07/06/07

Re: Atlas EQ6 kept drifting after slew new [Re: Bill W.]
      #6075438 - 09/11/13 03:59 PM

Quote:

They aren't round here...

-Bill




That's fine, but gear mesh causing his problem just doesn't make a lick of sense. Sorry.


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

Reged: 07/06/07

Re: Atlas EQ6 kept drifting after slew [Re: rmollise]
      #6075441 - 09/11/13 04:00 PM

Quote:

Quote:

They aren't round here...

-Bill




That's fine, but gear mesh causing his problem just doesn't make a lick of sense. Sorry.




And "after the slew" means after he got to the object it kept moving.


Post Extras: Print Post   Remind Me!   Notify Moderator  
Puck Ja
scholastic sledgehammer
*****

Reged: 11/21/12

Loc: OK, USA
Re: Atlas EQ6 kept drifting after slew new [Re: rmollise]
      #6109471 - 09/30/13 03:33 PM

Thanks guys for the input and "interesting" discussion on guessing what did I exactly mean.

The symptom was that the I assumed the scope finished the command (since it didn't beep as the hand controller did) and the stars in FOV still moves a continuously for a while.

After more carefully balance the mount at MULTIPLE orientation, and make sure that I ensure the level locks were tight. I have not seen such drifting anymore, even with the C11.

I guess that those two mentioned improvements are the keys to resolve such issue.

I hope this may help someone in the future!


Post Extras: Print Post   Remind Me!   Notify Moderator  
Pages: 1 | 2 | (show all)


Extra information
8 registered and 15 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: 800

Jump to

CN Forums Home


Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics