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

Is ASI1600mm right for my setup?

  • Please log in to reply
5 replies to this topic

#1 hyperion0001

hyperion0001

    Sputnik

  • -----
  • topic starter
  • Posts: 34
  • Joined: 26 Sep 2007
  • Loc: Concord, MA

Posted 23 October 2019 - 03:14 PM

I've decided I want to go from my DSLR to a CMOS or CCD camera, and want to pursue LRGB and narrowband imaging moving forward. I currently use my LX200R 10" SCT with an MyT mount. I image from my backyard in a small town - I barely make out the Milky Way at the zenith on good moonless nights, so seeing is not great but ok.

 

I've read a lot of good things about the ASI1600mm camera and am seriously considering it for my next foray into AP. 

Given what I've read, many say it's important to match up the camera properly with your system. So here I am. With an f/6.3 focal reducer, I expect to get about 0.32 arc seconds per pixel. With my Canon DSLR T3i, I get 0.4 arc seconds per pixel (before debayering) and have been getting very decent OSC images. This makes me think that I won't really benefit very much from the 0.32 arc seconds per pixel resolution on the mono camera. I've read oversampling is good for planetary but doesn't give you much for DSO imaging.

 

I'm thinking there are many other advantages to getting the ASI1600mm, so this isn't a deal breaker for me, just wondering if anyone had anything to say about it. Would it make sense for me to eventually run the mono camera with 2x2 binning as a regular thing? I have to say I feel like I'll be cheating myself, given the touted resolution advantages of moving from a OSC to a mono camera.

 

terry

 



#2 rgsalinger

rgsalinger

    Fly Me to the Moon

  • *****
  • Moderators
  • Posts: 5192
  • Joined: 19 Feb 2007
  • Loc: Carlsbad Ca

Posted 23 October 2019 - 03:40 PM

I occasionally image with my 1600 on a 2.5 meter scope which gives me .31 arc seconds of image scale. I bin the camera and reduce my exposures to just a minute or two. Seems to work OK.

Rgrds-Ross


  • hyperion0001 likes this

#3 gcardona

gcardona

    Mariner 2

  • -----
  • Posts: 233
  • Joined: 24 Nov 2009

Posted 23 October 2019 - 03:53 PM

I face a similar situation, in that my current camera, a QHY-12 has 5.12u pixels, which for me gives about 0.62"/pixel. I need to go to mono for the same reasons you mention, namely the ability to do narrowband efficiently. I am considering the ASI1600mm because there are really no other options unless I want to spend $$$$ on a CCD with large pixels that is going EOL. (On-Semi is discontinuing ALL of their CCD production.) The 1600 would give me about 0.32"/pixel, and the field of view slightly smaller (the QHY-12 has an APS size chip, like your DSLR.). I'm don't freak out about over-sampling, so I'm comfortable with the pixel size. The thing that I'll miss is the field of view, which is about 80% of the APS size chip.


  • hyperion0001 likes this

#4 hyperion0001

hyperion0001

    Sputnik

  • -----
  • topic starter
  • Posts: 34
  • Joined: 26 Sep 2007
  • Loc: Concord, MA

Posted 23 October 2019 - 04:56 PM

I occasionally image with my 1600 on a 2.5 meter scope which gives me .31 arc seconds of image scale. I bin the camera and reduce my exposures to just a minute or two. Seems to work OK.

Rgrds-Ross

Yes, I suppose the faster integration time on top of the higher sensitivity/cooling could be a significant advantage, effectively giving a factor increase in light exposure for a given exposure time. Thanks for acknowledging that...it's good to know my reading hasn't all been in vain :)

terry



#5 hyperion0001

hyperion0001

    Sputnik

  • -----
  • topic starter
  • Posts: 34
  • Joined: 26 Sep 2007
  • Loc: Concord, MA

Posted 23 October 2019 - 05:02 PM

I face a similar situation, in that my current camera, a QHY-12 has 5.12u pixels, which for me gives about 0.62"/pixel. I need to go to mono for the same reasons you mention, namely the ability to do narrowband efficiently. I am considering the ASI1600mm because there are really no other options unless I want to spend $$$$ on a CCD with large pixels that is going EOL. (On-Semi is discontinuing ALL of their CCD production.) The 1600 would give me about 0.32"/pixel, and the field of view slightly smaller (the QHY-12 has an APS size chip, like your DSLR.). I'm don't freak out about over-sampling, so I'm comfortable with the pixel size. The thing that I'll miss is the field of view, which is about 80% of the APS size chip.

Well, I went from my DSLR (which I'm still using) to an ASI385mc...talk about chip-size envy ...So bouncing back to the ASI1600 chip size is not so bad for me....it gets me closer to the DSLR at a pretty good price point, so I'm thinking that's what I'll do. I was just complaining that I wouldn't see that magical increase in detail everyone talks about when you go from the color to mono...just want to manage my expectations! I want to get some feeling for what I'm getting myself into once I pull the mono-trigger smile.gif

 

terry

P.S. I looked at some of your images...nice! Makes me wonder if I'm not jumping the gun on getting a mono camera. You seem to have done quite nicely with what you have.


Edited by hyperion0001, 23 October 2019 - 05:09 PM.


#6 gcardona

gcardona

    Mariner 2

  • -----
  • Posts: 233
  • Joined: 24 Nov 2009

Posted 23 October 2019 - 05:54 PM

I think the increase in detail comes from the fact that in a Bayer matrix chip, the resolution is effectively 1/4 of the stated resolution because of the interpolation used to fill in the colors in the de-bayering process. In a mono camera, you get full resolution for each color.




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