#1  
Old 06-01-2011, 03:41 PM
telemarker's Avatar
telemarker (Keith)
Registered User

telemarker is offline
 
Join Date: Mar 2008
Location: Canberra, Australia
Posts: 601
Question Sxv-AO mount bumping

Finally received a Lodestar camera to use with the AO unit. Managed to get the AO guiding for a max of 10 min before the guide star drifted outside the rectangle due to drift from polar misalignment. My question is how does one set up mount bumping with these units?

I was using an 8" SCT at f6.3 on an LXD75 mount with the ST-4 output from the AO fed into a 909 port autoguider. I've tried the SX lodestar program for guiding but it crashes on my vista laptop. Maxim works with the AO but this is where I have difficulties, how do you tell it to use the AO for bumping the mount? Any advice or experiences would be greatly appreciated.
Reply With Quote
  #2  
Old 06-01-2011, 06:15 PM
ericwbenson (Eric)
Registered User

ericwbenson is offline
 
Join Date: Sep 2009
Location: Adelaide, Australia
Posts: 199
OK, this is a real RTFM, but the answer for Maxim is the "Calibrate Drive" radio button on the locate tab of the main SX AO Control dialog. However bumping should be on by default in Maxim (see the Bump Time and Activation Level settings on the Drive tab), so make sure the mount is getting guider correction signals. You can test the guider signals with the regular guider controls on the CCD window (for example regular guiding or use the Move dialog).

Good luck,
EB
Reply With Quote
  #3  
Old 06-01-2011, 06:49 PM
multiweb's Avatar
multiweb (Marc)
ze frogginator

multiweb is offline
 
Join Date: Oct 2007
Location: Hinchinbrook
Posts: 18,140
Hi Keith, TBH I didn't bother with the mount bumping. I guide with a QHY5 on a finder separately and have the AO with the lodestar on the OAG doing its thing. It's a no brainer and it works.
Reply With Quote
  #4  
Old 07-01-2011, 07:40 PM
telemarker's Avatar
telemarker (Keith)
Registered User

telemarker is offline
 
Join Date: Mar 2008
Location: Canberra, Australia
Posts: 601
Thanks for the info guys. Well I had better do some reading then. In then interim, gave Marc's method a go. It seems to work OK but is sensitive to cloud, moreso than the finderguider which makes for some interesting star patterns. I'll keep playing with it.

Last edited by telemarker; 07-01-2011 at 09:33 PM.
Reply With Quote
  #5  
Old 07-01-2011, 08:07 PM
bert's Avatar
bert (Brett)
Automation nut

bert is offline
 
Join Date: Mar 2008
Location: Bathurst
Posts: 667
Hi Keith,

Take the time to do get it working properly with maxim drive calibration. I set the bumping threshold at 25%. The advantage of this is the ability to dither via ao in the autosave menu, which makes a huge difference to the noise characteristics in my camera. I personally set the bumping threshold at 25% of deflection.

If it is the same menu as the sbig ao in maxim, just choose mount calibration where you select 'find guide star' in the ao window.

HTH
Brett
Reply With Quote
  #6  
Old 09-01-2011, 04:41 AM
telemarker's Avatar
telemarker (Keith)
Registered User

telemarker is offline
 
Join Date: Mar 2008
Location: Canberra, Australia
Posts: 601
Thanks Brett, second go last night got it guiding for over an hour. Very neat when it ticking away and the stars were oh so round. My main battle is getting the calibration to work, it auto selects hot pixels and has a big whinge when they don't move. I can't for the life of me see how to dark subtract from the guider's image and only got around it by exposing for 10 sec at 4x4 binning where it'll select a star not the hot pixel.

Regards
Keith
Reply With Quote
  #7  
Old 10-01-2011, 09:38 PM
telemarker's Avatar
telemarker (Keith)
Registered User

telemarker is offline
 
Join Date: Mar 2008
Location: Canberra, Australia
Posts: 601
Just a quick image. NGC3576 30 min in 5 min subs using 127ED with Orion SSDSI and SXV-AO. No flats, stacked in DSS, PS for curves and levels.

One is full frame and the other is a 100% crop. Happy with the star shape and very little movement between subs. Now for some clear nights.
Attached Thumbnails
Click for full-size image (NGC3576_Loops_Test_AO_Crop.jpg)
156.7 KB45 views
Click for full-size image (NGC3576_Loops_Test_AO.jpg)
186.4 KB37 views
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 03:44 AM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
Lunatico Astronomical
Advertisement
Bintel
Advertisement
Meade Australia
Advertisement
NexDome Observatories
Advertisement
OzScopes Authorised Dealer
Advertisement
SkyWatcher Australia
Advertisement
Celestron Australia
Advertisement
Astronomy and Electronics Centre
Advertisement