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

Image issues with 8” SCT

  • Please log in to reply
29 replies to this topic

#26 alphatripleplus

alphatripleplus

    World Controller

  • *****
  • Moderators
  • Posts: 121,899
  • Joined: 09 Mar 2012
  • Loc: Georgia

Posted 13 April 2021 - 07:59 AM

Good news. Look forward to seeing the pics for comparison if/when you have a chance.



#27 GazingOli

GazingOli

    Messenger

  • -----
  • Posts: 408
  • Joined: 13 Oct 2019
  • Loc: Stuttgart GERMANY

Posted 13 April 2021 - 01:55 PM

Good info, Cey. I did not think that there is such a difference between the two focal reducers and I think not many people are aware of that.

 

CS.Oli



#28 Cey42

Cey42

    Explorer 1

  • -----
  • topic starter
  • Posts: 60
  • Joined: 17 Aug 2020
  • Loc: Kirkland, WA

Posted 13 April 2021 - 04:12 PM

First, like GazingOli, I did not expect to see that much difference between the Meade and Celestron reducers.

 

All I did was remove the Meade reducer and then attach the Celestron one. I did not change any of the spacing, so it was still at about 105mm. I ran the image through astrometry.net, then used the results to calculate my focal reduction. I am getting a reduction of .65. One interesting thing was that the focus was way off after the switch.

 

Here is the full image of M51. You can see that the coma is basically gone. The stars on the edge are not perfect circles but much better. The improvement was way more than I expected.

M51-4_12_2021-71x6s.jpg

 

 

Here is a close-up of the bottom right corner comparing both the Meade and Celestron reducers.

M51-Before-After.jpg

 

Thank you to those of you that suggested trying the Celestron reducer.

 

 

I am now happy with the image/star quality.

 

 

Thanks,
Cey


  • Jamez, GazingOli and bips3453 like this

#29 alphatripleplus

alphatripleplus

    World Controller

  • *****
  • Moderators
  • Posts: 121,899
  • Joined: 09 Mar 2012
  • Loc: Georgia

Posted 13 April 2021 - 06:38 PM

That is a big difference - thanks for posting the comparison.



#30 GazingOli

GazingOli

    Messenger

  • -----
  • Posts: 408
  • Joined: 13 Oct 2019
  • Loc: Stuttgart GERMANY

Posted 13 April 2021 - 11:47 PM

+1 Oli




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