Jump to content

  •  

CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.

Photo

Long exposure images not showing round stars..

  • Please log in to reply
25 replies to this topic

#26 DRNIK1987

DRNIK1987

    Lift Off

  • -----
  • topic starter
  • Posts: 15
  • Joined: 05 Oct 2021

Posted 03 December 2021 - 08:12 AM

I think your MnMo might be too high.  With the ZWO mini guide scope you’re at a few arc seconds per pixel, without looking up the pixel scale exactly, I’m going to guess its somewhere around 3-5 arc seconds or so per pixel, maybe more, which means your mount won’t be sent a correction pulse until it’s quite a ways off(for instance, if you were at 5 arc seconds per pixel, that means phd won’t send a correction until the scope has drifted a whole arc second off course with your setting of 0.20), potentially enough to cause trailing.  Then I was using that guide scope, I had MnMo set really low, to 0.05.  I was at over 7 arc seconds per pixel with my 174mm.  It looks as if the mount is only correcting for very large spikes.  Try lowering the MnMo and see if it helps, you never know, it could be as easy as a setting.  If you haven’t done so already, I’ll calculate your pixel scale for your guide setup later when I have some more time, that way you can convert the MnMo number of pixels to arc seconds.  That gives you a much better feel for where it should be set at. You want it to be a bit less than your imaging pixel scale.  

Makes sense to me... Let me try this and give feedback to you in a Few days....!!!


  • Professor2112 likes this


CNers have asked about a donation box for Cloudy Nights over the years, so here you go. Donation is not required by any means, so please enjoy your stay.


Recent Topics






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics