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

Which camera for EAA and livestreaming with dobsonians?

  • Please log in to reply
8 replies to this topic

#1 Mario_S

Mario_S

    Lift Off

  • -----
  • topic starter
  • Posts: 18
  • Joined: 09 Jan 2021
  • Loc: Austria, Europe

Posted 14 July 2021 - 03:26 PM

Hello!

 

I am looking for a camera for EAA and livestreaming (often both together) through my dobsonian telescopes (200/1200 and 400/1680).

 

As a teacher, I regularly livestream through my telescope for my students since Corona. I currently use my ZWO ASI 178 MC for this. Unfortunately, this does not work out well because the field of view is too small for most objects.

 

Therefore I would like to buy a new camera, which I can use in the future for the livestreams and EAA.

 

Which camera would you currently recommend me?

Is a cooled camera still an advantage for EAA with short exposures or can I do without it?
Since I have a dealer here where I get a discount on ZWO ASI cameras, I would prefer a camera from ZWO.

 

I look forward to your tips on which camera is best here,
Mario

 


Edited by Mario_S, 14 July 2021 - 03:42 PM.


#2 GaryShaw

GaryShaw

    Apollo

  • *****
  • Posts: 1,311
  • Joined: 28 Nov 2017
  • Loc: Massachusetts / Wyoming

Posted 14 July 2021 - 04:21 PM

Hi

The ASI 294mc is a great camera with a pretty wide field of view but I don’t know, of course, what FOV you are looking to have. I’d suggest you go to Astronomy tools’ website and ‘model’ various cameras and input your dob’s FL and aperture into the online FOV calculator. Be sure to select ‘Imaging’ at the top: heres a link 

 

https://astronomy.to.../field_of_view/

 

I don’t know how you do EAA observing with a dob but your exposures must be very short so a cooled camera would seem unnecessary - unless you plan other activities with longer 30 sec+ exposures such as AP. If you fi find you get a few hot pixels, just capture and apply darks with Sharpcap and that will eliminate them. 
Good Luck

Gary


  • GazingOli and Mario_S like this

#3 Mario_S

Mario_S

    Lift Off

  • -----
  • topic starter
  • Posts: 18
  • Joined: 09 Jan 2021
  • Loc: Austria, Europe

Posted 14 July 2021 - 05:12 PM

Thanks for your answer!

 

I am concerned about significantly more field of view than with the ZWO ASI 178.

The field of view of the 294 is certainly more than sufficient!

 

With the dobsonians, to keep the stars round, I need to expose well under a second. I usually run them at 0.3 to 0.5 seconds per exposure when livestacking.

So a lot of images, but with a very short exposure time.

 

Darks in Sharpcap are no problem, I do that of course.

 

So is the 294 MC recommendable? Sounds good!
What do the others say about it?

 

Thanks and greetings,
Mario


Edited by Mario_S, 14 July 2021 - 05:12 PM.


#4 Ptarmigan

Ptarmigan

    Lagopus lagopus

  • *****
  • Posts: 5,027
  • Joined: 23 Sep 2004
  • Loc: Arctic

Posted 14 July 2021 - 06:52 PM

I have the ASI294mc Pro and very pleased with it. It is sensitive and gets the job done. cool.gif


  • Mario_S likes this

#5 MunichAtNight

MunichAtNight

    Explorer 1

  • -----
  • Posts: 62
  • Joined: 04 Dec 2020
  • Loc: Munich - Germany

Posted 14 July 2021 - 08:09 PM

Hello Mario!

 

I use the ASI183MC and ASI294MC uncooled with a Skywatcher 130 PDS Newton f/5 and I am very satisfied with both of them. ASI294MC (4144 x 2822 px) with a bigger sensor is much more sensitive than the ASI183MC (5496 x 3672 px).

 

EAA Setup Skywatcher 130PDS
 
Here some of my stacks I did with the ASI294MC
 
M51
M51 ALL Stack 229frames 1832s V4

 

 

 
M101
M101 ALL Stack 803frames 3212s

 

 
M106
M106 ALL Stack 530frames 4240s

 

 

As having in my actual f/5 EAA Setup only a 5" mirror I would suggest under any circumstances for a setup with small mirror the ASI 294MC.

 

By the way, at the standpoint of view to improve signal noise effects, cooling is to my knowledge just a rumour and the effect is nearly not existing. Very interesting for understanding how "useless" or "not important" cooling is will be shown in this linked video, where CEO Robin Glover from Sharcap explain it in detail.The only advantage of cooling in my understanding with EAA is that it will allow you to operate the camera under fixed conditions. Normally it makes sense to have been done the darks with same condition, parameters and identical temperature as the standard photos. So cooling to a fixed temperature may help. I just have a library with darks, done with different temperatures and up to now I couldn't see any problem even when temperature is somehow different. Many users claim about amp-glow special with the asi294MC where cooling may help. But this is more a problem when you do long time exposures. So again for an EAA setup cooling is not an important feature.

 

I will get shortly for my 10" Dobson Newton f/5 an EQ platform and I am very excited to test both cameras with the 10" mirror which is able to spend much more light than my small 5" newton. And in the moment, not having done any real testing, I feel with the big newton the ASI183MC can be a perfect camera with bigger resolution. But in the end it is always a personal feeling and how you work with it and what you want to see. I am sure with the ASI294MC you are not doing any thing wrong!

 

Hopefully within a short time a can deliver real facts by comparing both cameras with a 10" Newton and not just a feeling!

 

Kind regards from Munich - MunichAtNight - Ewald


Edited by MunichAtNight, 14 July 2021 - 08:16 PM.

  • Ptarmigan, xvariablestarx, GaryShaw and 2 others like this

#6 dcweaver

dcweaver

    Mariner 2

  • -----
  • Posts: 268
  • Joined: 12 Jul 2020
  • Loc: Silicon Valley

Posted 15 July 2021 - 12:39 AM

Check the backfocus requirements of any camera and make sure you can reach focus.  Some Dob mounted Newts don't have enough inward travel of the focuser.  Imaging Newts on the other hand have the focuser set closer to the primary which pushes the focus point out of the tube more.

 

Sounds like you have had some previous success, but worth checking to make sure a new camera will play nice with the Dob.


Edited by dcweaver, 15 July 2021 - 12:43 AM.

  • Mario_S likes this

#7 MunichAtNight

MunichAtNight

    Explorer 1

  • -----
  • Posts: 62
  • Joined: 04 Dec 2020
  • Loc: Munich - Germany

Posted 15 July 2021 - 05:02 AM

Hello!

 

Check the backfocus requirements of any camera and make sure you can reach focus.  ...

that's right! An important point to think about. With ASi294MC the distance from top level of the front glass of the camera until the chip surface is 6.5 mm. Compared to a "normal" camera as a Canon, Nikon, Olympus it is really very small. To get my Olympus OM-D with my 10" Dobson Newton in focus I had hard to struggle and I could only accomplish it with an extra small T-minus adapter. But with the ASI294MC it was with my Dobsonian newton no problem, I needed only an additional T2 spacer ring between camera and the focal 2" adapter. But I found it a nightmare to have for the spacer ring the correct diameter and correct gender. Male works only with female and otherwise round. wink.gif  And what I had had on stock at my home based on Murphys law was male to male, female to female and T2-42mm won't fit to 48 mm! But to be serious and dcweaver is right, it could be a distance problem in detail, only hard to solve and it is worth checking before buying a camera and discover that you need a new newton as well! shocked.gif

 

MunichAtNight - Ewald


Edited by MunichAtNight, 15 July 2021 - 05:05 AM.


#8 Mario_S

Mario_S

    Lift Off

  • -----
  • topic starter
  • Posts: 18
  • Joined: 09 Jan 2021
  • Loc: Austria, Europe

Posted 15 July 2021 - 07:17 AM

Thanks for the tips!

I have already tried EAA it with my ZWO ASI 178 MC.
The focus is not a problem here, I still have over 3 centimeters to focus.
I think the focus will not be that different between the different ZWO ASI cameras, right?

 

Mario


Edited by Mario_S, 15 July 2021 - 07:19 AM.


#9 GaryShaw

GaryShaw

    Apollo

  • *****
  • Posts: 1,311
  • Joined: 28 Nov 2017
  • Loc: Massachusetts / Wyoming

Posted 15 July 2021 - 07:31 AM

Just a small clarification that the ‘back focus’ is set by the telescope not by the camera. Most normal newtonians have a 55mm distance to the sensor. I’m not sure how dobs work that but you seem to have enough adjustment to reach focus. The ZWO product info shows a variety of ways to achieve the proper back focus.




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