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

11 '' RASA or RC, whose edge stars are better?

  • Please log in to reply
2 replies to this topic

#1 Padma Boy

Padma Boy

    Vostok 1

  • -----
  • topic starter
  • Posts: 183
  • Joined: 19 May 2018
  • Loc: China, chong qing

Posted 16 December 2019 - 02:05 AM

11 '' RASA or RC, whose edge stars are better, I need images for comparison. I am ready to buy GSO RC12 '' or RASA 11 '',Very hesitant, one is F2.2, GSO RC can only reach F6



#2 james7ca

james7ca

    Cosmos

  • *****
  • Posts: 7,749
  • Joined: 21 May 2011
  • Loc: San Diego, CA

Posted 16 December 2019 - 02:19 AM

Well, the RC will require a field flattener so that kind of makes the comparison difficult. Meaning, it depends upon how well the flattener works on the RC.

 

Also, the image scales are going to be wildly different, so again that will make any direct comparison pretty hard.

 

Really, these are two different kinds of instruments. The RASA is an extremely fast system corrected over its intended field, while the RC is moderately fast and requiring a flattener to produce anything close to the field coverage that is produced natively by the RASA. Then, mix in the image scale differences and you are about as far apart as one can be in comparing two imaging systems.

 

Trying to rate or grade these systems would be easier if you defined what kind of objects (DSOs) you are most interested in imaging. Also, any idea on the mount and the camera that you would be trying to use?


  • bobzeq25 likes this

#3 sg6

sg6

    Fly Me to the Moon

  • *****
  • Posts: 6,635
  • Joined: 14 Feb 2010
  • Loc: Norfolk, UK.

Posted 16 December 2019 - 04:18 AM

I would say just about impossible. Both seem to need critical "collimation". Someone I know has an RC and has spent close to a year getting it effectively perfect. They are a bit obsessive. Maybe more then a bit but their images are supurb.

 

So if one arrives a bit less well set up it will show worse.

 

When you get to scopes as critical as these a lot will depend on your input.




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