backlash, apcc, ap v2, gtocp4, new gear mesh mounts


dave@...
 

The posts about guiding and backlash got me thinking about the apcc/ap v2 settings for backlash in the new mounts. quick question.

Do the newer mounts not use software to compensate for backlash? Is there no backlashin the newer mounts or do you physically remove backlash via the gearbox? Or is the backlash removed via the spring loaded gearbox? Maybe something else?

Thanks.

Dave.


Michael Fulbright <mike.fulbright@...>
 

I'd be surprised if you would ever see problems with RA backlash if you have the worm mesh properly set - and then only if you slew or manually move the mount East at a speed faster than sidereal tracking.  Depending on the RA weight bias then you might see some backlash as the worm tries to catch up and track West again.  On cheaper mounts you can set a balance bias to the East to alleviate this problem but on an AP mount I can't imagine that would be required.

Since the RA motor never changes direction when tracking/guiding you simply cannot see backlash.  When you guide East it simply slows down or stops the RA tracking temporarily (for guide speeds up to 1x sidereal - I can't imagine ever going faster than 1x).

Michael Fulbright

On 4/23/2017 2:21 PM, dave@... [ap-gto] wrote:
 

The posts about guiding and backlash got me thinking about the apcc/ap v2 settings for backlash in the new mounts. quick question.

Do the newer mounts not use software to compensate for backlash? Is there no backlashin the newer mounts or do you physically remove backlash via the gearbox? Or is the backlash removed via the spring loaded gearbox? Maybe something else?

Thanks.

Dave.



dave@...
 

I ask because of the appc and ap v2 driver setting to remove backlash (gto cp3 only). Why not with the gto cp4? You can use a cp4 with older mounts as well so it can't be the new gear box.

I see now on the ap website that the backlash setting was for manual guiding back in the day:

"Does not have R.A. and Declination backlash control. This was initially designed for manual guiding."

Thanks

Dave


Ray Gralak
 

Dave,

The driver and apcc don’t have backlash controls for the cp4 because the backlash correction commands were removed from the cp4. I think the reason was that people would sometimes set the backlash value incorrectly and that was causing guiding problems. A-P has been recommending a 0 backlash setting for some time, so this essentially enforces that recommendation with the CP4.

-Ray Gralak
Author of APCC (Astro-Physics Command Center): http://www.astro-physics.com/index.htm?products/accessories/software/apcc/apcc
Author of PEMPro: http://www.ccdware.com
Author of Astro-Physics V2 ASCOM Driver: http://www.gralak.com/apdriver
Author of PulseGuide: http://www.pulseguide.com
Author of Sigma: http://www.gralak.com/sigma

-----Original Message-----
From: ap-gto@... [mailto:ap-gto@...]
Sent: Sunday, April 23, 2017 3:15 PM
To: ap-gto@...
Subject: Re: [ap-gto] backlash, apcc, ap v2, gtocp4, new gear mesh mounts



I ask because of the appc and ap v2 driver setting to remove backlash (gto cp3
only). Why not with the gto cp4? You can use a cp4 with older mounts as well so it
can't be the new gear box.

I see now on the ap website that the backlash setting was for manual guiding back
in the day:

"Does not have R.A. and Declination backlash control. This was initially designed
for manual guiding."

Thanks

Dave


dave@...
 

I see now on the ap website that the backlash setting was for manual guiding back in the day and was removed from the cp4:

"Does not have R.A. and Declination backlash control. This was initially designed for manual guiding."

Thanks

Dave


Roland Christen
 

Backlash in our latest spring loaded gearbox is vanishingly small. It is not an issue in RA for guiding in any case. As far as Go-To, the mount will move to within an arc sec or 2 of where you command it in both axes.

Rolando



-----Original Message-----
From: dave@... [ap-gto]
To: ap-gto
Sent: Sun, Apr 23, 2017 1:21 pm
Subject: [ap-gto] backlash, apcc, ap v2, gtocp4, new gear mesh mounts

The posts about guiding and backlash got me thinking about the apcc/ap v2 settings for backlash in the new mounts. quick question.

Do the newer mounts not use software to compensate for backlash? Is there no backlashin the newer mounts or do you physically remove backlash via the gearbox? Or is the backlash removed via the spring loaded gearbox? Maybe something else?

Thanks.

Dave.

------------------------------------
Posted by: dave@...
------------------------------------

To UNSUBSCRIBE, or for general information on the ap-gto list
see http://groups.yahoo.com/group/ap-gto
------------------------------------

Yahoo Groups Links

<*> To visit your group on the web, go to:
http://groups.yahoo.com/group/ap-gto/

<*> Your email settings:
Individual Email | Traditional

<*> To change settings online go to:
http://groups.yahoo.com/group/ap-gto/join
(Yahoo! ID required)

<*> To change settings via email:
ap-gto-digest@...
ap-gto-fullfeatured@...

<*> To unsubscribe from this group, send an email to:
ap-gto-unsubscribe@...

<*> Your use of Yahoo Groups is subject to:
https://info.yahoo.com/legal/us/yahoo/utos/terms/