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

DSO imaging on a very tight budget

  • Please log in to reply
8 replies to this topic

#1 DennyD

DennyD

    Lift Off

  • -----
  • topic starter
  • Posts: 4
  • Joined: 05 Jan 2020

Posted 19 September 2020 - 02:18 PM

I'm new to astrophotography and made the change from using my smartphone to a dedicated astrophotography camera. My telescope is a Meade ETX-90RA with a ZWO ASI120MC-S and Nikon D40 DSLR. As much as I'd like to upgrade from the ASI120MC-S to an ASI224MC, my budget won't allow for that. Is the ASI120MC-S a good camera for DSOs? I do plan to get a .5 focal reducer to use with it. Any thoughts, help, and advice would be greatly appreciated. Denny.

#2 Shelldrake

Shelldrake

    Explorer 1

  • -----
  • Posts: 72
  • Joined: 06 Oct 2015
  • Loc: Halifax, Nova Scotia, Canada

Posted 19 September 2020 - 02:35 PM

Although you can use your ASI120MC-S to image small DSOs (I went this route when I first started astrophotography - see attached images), it is not optimal as this OSC camera is really meant for planetary imaging. In this regard, you will not gain anything upgrading to an ASI224MC. You may not be able to reach focus with a .5 focal reducer and the ASI120MC-S. This combination did not work with my ST80 refractor. In any case, your Nikon DSLR will give you better results on galaxies and star clusters although emission nebula really need an astro-modified DSLR.

David

 

Attached Thumbnails

  • Collage.jpg

  • drd715 likes this

#3 sg6

sg6

    Cosmos

  • *****
  • Posts: 9,028
  • Joined: 14 Feb 2010
  • Loc: Norfolk, UK.

Posted 19 September 2020 - 02:44 PM

First thought is the Meade 90RA is not the best scope.

For DSO imaging the 90RA is going to be difficult, even with a 0.5 reducer - is there such a thing for the 90RA ?

 

I think the 120MC is a small sensor so target selection will be important.

 

My "fear" is that in buying items to get around the problem of using a 90RA you are diverting money from a potentially easier and better setup.

 

How much would a 120MC and a reducer cost - just approximate?

Would the budget for those cover a small but reasonable equitorial mount?

 

Often in this gane it is a case of you just need to acceot that you need the "right" equipment. I could not image planets, nothing I have is really suitable - small but good refractors. I am not going to try and work around it with barlows and extenders etc as basically they are "wrong".

 

Years ago I knew a group that imaged with basic equipment: EQ5's, 72mm ED refractors (Megrez 72's at that time) and DSLR's. Some added a flattener. But that was a useable and decent basic imaging setup. Honestly suggest you think of something along those lines. Maybe a WO ZS 61 as the scope.

 

I know it will cost but trying to make a 90RA do something it is not suited for is not an ideal approach.

I suggest time to sit and think.

 

If your DSLR will fit now on the 90RA I would just attempt to get along with that and spend nothing for a while and think it all through.



#4 DennyD

DennyD

    Lift Off

  • -----
  • topic starter
  • Posts: 4
  • Joined: 05 Jan 2020

Posted 19 September 2020 - 03:00 PM

Thank you, and some very good points. I'll stay with the ASI120MC-S and Nikon D40 DSLR, and won't get the focal reducer.

#5 Achernar

Achernar

    Voyager 1

  • *****
  • Posts: 11,787
  • Joined: 25 Feb 2006
  • Loc: Mobile, Alabama, USA

Posted 19 September 2020 - 03:25 PM

There is no way to successfully image deep sky objects with long exposures while spending a pittance. A budget set up for deep sky objects would be a basic mounting such as Celestron's AVX, and a 80mm apochromatic refractor, like the basic model still sold by Orion Telescope and binoculars. If your DSLR has an APS sized chip, it might work very well without a field flattner, which Orion does sell a fairly inexpensive one that could be used with this telescope. But if stars are only slightly out of round at the corners, who cares? Perfection costs a lot of money, good enough a lot less. You need a guide scope, which your ZWO ASI 120 camera could be inserted into and used as an auto-guider. If you bought all of this new, it would come to $2,000 or more, and it will only work well for larger DSO's and comets when they get big and bright like NEOWISE recently. There is however some You Tube videos about astrophotography on a budget, and you can find them by typing astrophotography on a budget in You Tube's search function. Before you spend any money, research, shop and compare. You can possibly acquire everything you'll need on the used market.

 

Taras


Edited by Achernar, 19 September 2020 - 03:29 PM.


#6 klaussius

klaussius

    Viking 1

  • *****
  • Posts: 736
  • Joined: 02 Apr 2019
  • Loc: Buenos Aires

Posted 19 September 2020 - 04:45 PM

Years ago I knew a group that imaged with basic equipment: EQ5's, 72mm ED refractors (Megrez 72's at that time) and DSLR's. Some added a flattener. But that was a useable and decent basic imaging setup. Honestly suggest you think of something along those lines. Maybe a WO ZS 61 as the scope.
I started with an EQ5 dual axis, a Celestron Travelscope 70 (a cheap 70mm achromat) and a DSLR (used Canon 650D).
 
I think that's about as cheap as it gets where you get some chance for success. I tried with cheaper stuff and got nowhere.
 
The ASI120 is a good planetary and guide camera. For guiding the mono version is better, but the color version will do if that's what you've got. I wouldn't use it for DSO, because the chip is tiny and has a tiny FOV. It would only work for very small DSOs, and those are hard to image, not the best targets for learning.
 
You can do a lot with a stock DSLR. Astro-modding would be recommended but it's not absolutely necessary.
 
A flattener is required for really good images, but you can learn a lot and get some decent images without it. I would suggest skipping the flattener if your budget is tight. They're expensive, and scope-specific, so you want to buy one for the scope you'll be using a long time, not your starter scope.
 
A good, cheap option to start imaging DSOs is to forget about a scope and use lenses. But that assumes you've got a decent long lens, like a 135mm or 200mm prime lens. If you do, get a tracker and use it, it's going to be far cheaper than trying to get an entry-level eq mount, ED scope and flattener, and all the accessories that go with them.


#7 Stelios

Stelios

    Voyager 1

  • *****
  • Moderators
  • Posts: 10,234
  • Joined: 04 Oct 2003
  • Loc: West Hills, CA

Posted 19 September 2020 - 05:23 PM

I'm new to astrophotography and made the change from using my smartphone to a dedicated astrophotography camera. My telescope is a Meade ETX-90RA with a ZWO ASI120MC-S and Nikon D40 DSLR. As much as I'd like to upgrade from the ASI120MC-S to an ASI224MC, my budget won't allow for that. Is the ASI120MC-S a good camera for DSOs? I do plan to get a .5 focal reducer to use with it. Any thoughts, help, and advice would be greatly appreciated. Denny.

You may be able to use the ETX-90RA for planetary imaging (you'll probably want a Barlow). 

 

But for DSO, both the scope and the camera are about as bad choices as possible. For DSO you need a steady mount, you need relatively fast F/ratios, and you want cameras with large FOV (field of view). Your equipment is almost the opposite of that. You might try some small planetary nebulae, but don't buy the reducer (which will perform poorly for photography), if you're seriously interested in the hobby I would get rid of the ETX-90RA and the ASI120MC-S and save for an iEXOS-100 mount and put my DSLR on it (initially) and a small scope (eventually, when budget allows). Good luck!



#8 bobzeq25

bobzeq25

    ISS

  • *****
  • Posts: 21,388
  • Joined: 27 Oct 2014

Posted 19 September 2020 - 07:05 PM

I'm new to astrophotography and made the change from using my smartphone to a dedicated astrophotography camera. My telescope is a Meade ETX-90RA with a ZWO ASI120MC-S and Nikon D40 DSLR. As much as I'd like to upgrade from the ASI120MC-S to an ASI224MC, my budget won't allow for that. Is the ASI120MC-S a good camera for DSOs? I do plan to get a .5 focal reducer to use with it. Any thoughts, help, and advice would be greatly appreciated. Denny.

Tight budget and DSO astrophotography equals camera tracker/camera lens/camera.  Period.

 

Adding a scope doesn't help make things better, it just makes them very expensive.  Shortening the focal length makes things (like the all important mount), _much_ cheaper.

 

This book is a great guide.

 

https://www.astropix...bgda/index.html


Edited by bobzeq25, 19 September 2020 - 07:06 PM.


#9 DMRandall

DMRandall

    Vostok 1

  • -----
  • Posts: 105
  • Joined: 25 Dec 2008

Posted 19 September 2020 - 09:56 PM

I have to agree with bobzeq25.  I had an ETX90, and even a DSLR (as well as the old Meade LPI, and a Meade DSI) and none of them were at all good for DSO's.  I gave it a try, many times, and was always disappointed.  Camera tracker (like the SkyWatcher Star Adventurer) plus a DSLR and a mid-range telephoto lens - 200 or 300mm can go a long ways.   


  • 17.5Dob and bobzeq25 like 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