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

First light with the last (?) CEM60

  • Please log in to reply
4 replies to this topic

#1 mborland

mborland

    Explorer 1

  • -----
  • topic starter
  • Posts: 65
  • Joined: 17 Mar 2020
  • Loc: Chicago

Posted 05 July 2020 - 10:13 PM

I recently purchased what may well be the last new CEM60 in the US. I was happy to get it as I needed something with a good weight/load ratio and wanted higher capacity (and non-EC) compared to my CEM40EC. The CEM70 is 10% heavier and too new. Having used a CEM40EC for a few months, I found the CEM60 easy to learn and use.

 

My first target was the Crescent Nebula, which I imaged over three nights from my Bortle 8 Chicago suburbs location. Included are 39 x 180s and 58 x 360s for a total of 7.75 hours. Other details: iOptron Tri-Pier on a concrete driveway, iPolar, Meade 8" LX90 ACF, ASI 071 MC Pro at -10C, ASI 290 MM Mini on ZWO OAG, Optolong LEnhance. Software: APT, PHD2, PixInsight.

 

CrescentNebula-2020-06-20s.jpg

Bigger version:

https://flic.kr/p/2jdy1FC

 

Compared to the CEM40EC carrying the same equipment, I get noticeably rounder stars, which was one of my goals with the CEM60. I'm getting about 30% higher rms in RA than in DEC (0.32" and 0.25" are typically) and unsure what to do about that. Seeing was not great, but not the worst I've seen. I'm hoping eventually move up to an 11" Edge HD on the same mount. I use the PPEC algorithm in PHD2 for RA and bin the ASI290MM, which seems to help, but the OAG often gives distorted star images even when focused. Is this normal with an ACF scope?

 

Alas, last week the RA stopped moving on my CEM60. After discussion with iOptron support and help from OPT (the retailer), I got a new RA board from iOptron and it is up and running same as before.

 

--Michael


  • artem2, lbim, Gipht and 3 others like this

#2 imtl

imtl

    Viking 1

  • *****
  • Posts: 684
  • Joined: 07 Jun 2016

Posted 05 July 2020 - 10:28 PM

The RA and DEC numbers you are getting are well within seeing limits especially from where you image. I would not worry about that at all. It will not show in your images. If you decide to move to a 11" Edge then start thinking about it. But you will have bigger issues to think about when you go for the 11"...



#3 mborland

mborland

    Explorer 1

  • -----
  • topic starter
  • Posts: 65
  • Joined: 17 Mar 2020
  • Loc: Chicago

Posted 05 July 2020 - 10:35 PM

The RA and DEC numbers you are getting are well within seeing limits especially from where you image. I would not worry about that at all. It will not show in your images. If you decide to move to a 11" Edge then start thinking about it. But you will have bigger issues to think about when you go for the 11"...

I'm hoping some day to retire and move to Arizona, *then* get the 11" Edge HD. lol.gif

 

--Michael

 



#4 imtl

imtl

    Viking 1

  • *****
  • Posts: 684
  • Joined: 07 Jun 2016

Posted 05 July 2020 - 11:33 PM

Arizona is indeed great but it is not without its problems in matters of imaging.

Summers are hot during the night as well and monsoons are governing the weather.

Winter however......

 

Just stay away from Phoenix.



#5 yzhzhang

yzhzhang

    Viking 1

  • *****
  • Posts: 818
  • Joined: 13 Dec 2012
  • Loc: San Diego, CA

Posted 06 July 2020 - 12:53 AM

Congrats on he new mount. Seems getting the job done. That's really really good RMS for guiding if you ask me... You rarely achieve that kind of guiding under imaging condition you described. I would double check guiding input just to make sure they are real, but if stars turn out good then no worries I guess.


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