Jump to content

Stargazers Lounge Uses Cookies

Like most websites, SGL uses cookies in order to deliver a secure, personalised service, to provide social media functions and to analyse our traffic. Continued use of SGL indicates your acceptance of our cookie policy.

sgl_imaging_challenge_banner_through_the-_eyepiece.thumb.jpg.cb85f690376dcb3053c747827de6bf9e.jpg

astro mick

Dual rig ccd cameras

Recommended Posts

Hi guys.

Am setting up a dual rig comprising of dual ED 80 F7.5 scopes.

One for mono and one for RGB.

Already have an Atik 314L+ possibly for mono.

To keep costs down looking at the Atik 420E for the RGB.

I know they are different sized chips,and the 420E is more suited to fast scopes.

Yout thoughts again please.

Mick.

 

Share this post


Link to post
Share on other sites

If you can, get another 314 (2nd hand). Its a rig I used to have and it generated a lot of data, pretty quickly.

However, one point to note is that unless you have an adjustable saddle for the 2nd scope - youre going to be using guidescope rings... which I always thought the 80ED was a little bit heavy for. Great when it works, but if the alignment goes off a bit - its a case of fiddling about in the dark to fix it.

With two mono cameras you can still capture the Lum and colour at the same time, just run it this way... for every 3x600 of Lum, you will have 1x600 in R,G and B - which would be good enough ratio of Lum and RGB for a decent LRGB image. However that would also involve an EFW (more expense... sorry!...lol).

Share this post


Link to post
Share on other sites

Hi Mick,

I've no experience of the 420E, but I do have a mono and OSC camera with the same chip in, and sometimes use the data together, which works quite well, although I don't capture the data simultaneously. (Can't afford two 6" 'fracs! :p )

At any rate, even if your RGB data is a different size or resolution, you can make it fit together nicely with a program called Registar, which can work on images with even a vastly different scale. As long as you are adjusting the RGB data to suit the Luminance set you shouldn't have too many issues.

It's an interesting project, keep us updated with how you get on :)

 

Tim

Share this post


Link to post
Share on other sites

Have you already got the 2nd scope?

If not you may or may not be interested in my set up.  

I don't have matching scopes or cameras but if I put my smallest camera in my widest field scope, and vcie versa the FOV comes up almost matching.  This gives me lots of versatily, as I can put the largest FOV camera in the widest FOV scope for large targets and vice versa for small objects.

Dual rig is: 

ED80 and Atik460

WOZS71 and Atik314L

These are pretty similar FOV done together.

HTH

Carole 

Share this post


Link to post
Share on other sites

My dual rig incorporates an OSC ccd camera on one scope and a HaOiiiSiiLRGB mono setup on my second scope. I gather RGB on one scope and usually Lum or Ha on the other scope. It gives me full flexibility on broadband or narrowband imaging. I calibrate and combine my images, which have different fov using APP.

Steve

  • Like 1

Share this post


Link to post
Share on other sites
12 hours ago, carastro said:

Have you already got the 2nd scope?

If not you may or may not be interested in my set up.  

I don't have matching scopes or cameras but if I put my smallest camera in my widest field scope, and vcie versa the FOV comes up almost matching.  This gives me lots of versatily, as I can put the largest FOV camera in the widest FOV scope for large targets and vice versa for small objects.

Dual rig is: 

ED80 and Atik460

WOZS71 and Atik314L

These are pretty similar FOV done together.

HTH

Carole 

Hi Carol.

Yes i have two of those discontinued Celestron ED 80 F7.5.

These are great scopes with R/P focusser, image never shifts no matter what the weight.I believe also they use FPL-53 glass.(crude but efective)

Mick.

Mounting piggy back.

Share this post


Link to post
Share on other sites

Thanks to eveyone else who commented.

Mick.

Share this post


Link to post
Share on other sites

Good luck with the dual rig, please keep us posted on how you get on. I am planning a collaborative project using a Moravian G2-8300 mono on an Esprit 150 and a 314 OSC on an Altair 102 mm APO. This is not a considered choice, it’s just what cameras and scopes we have at this time. General consensus is that the mismatch in aperture will not allow the data to be combined successfully, but there’s no harm in trying.

Share this post


Link to post
Share on other sites
Posted (edited)
5 minutes ago, tomato said:

Good luck with the dual rig, please keep us posted on how you get on. I am planning a collaborative project using a Moravian G2-8300 mono on an Esprit 150 and a 314 OSC on an Altair 102 mm APO. This is not a considered choice, it’s just what cameras and scopes we have at this time. General consensus is that the mismatch in aperture will not allow the data to be combined successfully, but there’s no harm in trying.

If you use the software registar you will.Its a great piece of software that does all for you.

Mick.

Edited by astro mick

Share this post


Link to post
Share on other sites

Thanks Mick. You are quite correct, I’m sure both Registar or APP will size and align the images, apparently the problem could be that the larger aperture instrument goes a lot deeper, and stacking subs with such differing star counts makes for very poor images.

Anyway, we’ll give it a go.

Share this post


Link to post
Share on other sites

I ran three ED80s simply bolted down. It's easy to adjust one ring 'sideways' (Dec) to match the FOV of the other. Then I used tinfoil to make shimmy bits for 'up and down' (RA) if that makes sense.

I got fairly close. I got some adjustable saddles from FLO but never got to try them out before breaking the rig down. May or may not be better.

/Jesper

Share this post


Link to post
Share on other sites

I filed the base of a ring instead of adding shims. Fiddly but effective on my twin ED80s. 

Share this post


Link to post
Share on other sites

The idea of dual scopes on one mount is an attractive idea but not easy to do well. I did succeed with a TEC180 and TEC140 on an MEII after years of experimentation and specialized software. I guess it all depends on how far you want to push things! If you want to expose for very long (say 5 min +) the almost insurmountable problem will be differential flexure between the two scopes as only one of the OTAs can be guided. This can be overcome by using AO on the second scope and disabling mount corrections - the AO corrects for the DF. Another issue is one of dithering. To dither the cameras must be synchronized. Tom How wrote some wonderful software for me that does this and more: http://astro.neutral.org/software/astronomy-software.html. Other issues concern filter changes and automation. It can all be done but can become exceedingly complex. Once you start down this path it can be hard to stop. Good luck!

Peter

Share this post


Link to post
Share on other sites
Posted (edited)
3 hours ago, prejto said:

The idea of dual scopes on one mount is an attractive idea but not easy to do well. I did succeed with a TEC180 and TEC140 on an MEII after years of experimentation and specialized software. I guess it all depends on how far you want to push things! If you want to expose for very long (say 5 min +) the almost insurmountable problem will be differential flexure between the two scopes as only one of the OTAs can be guided. This can be overcome by using AO on the second scope and disabling mount corrections - the AO corrects for the DF. Another issue is one of dithering. To dither the cameras must be synchronized. Tom How wrote some wonderful software for me that does this and more: http://astro.neutral.org/software/astronomy-software.html. Other issues concern filter changes and automation. It can all be done but can become exceedingly complex. Once you start down this path it can be hard to stop. Good luck!

Peter

I'm surprised by these problems, Peter, and don't think they will apply to Mick's ED80s.

Our dual rig, consisting of 2xTak FSQ106Ns, just bolted together like a bit of flatpack shelving and worked perfectly from the off. All dead simple. We were helped by using a Cassady TGAD tilt-pan device for aligning the scopes but FLO now do a decent alternative. I didn't fancy shimming and fiddling! We guide via guidescope and I can see no reason why having two scopes rather than one would make any difference so far as diff flexure goes. It makes none in our case. You do want a serious quality side by side plate and good tube rings.

Re cameras, I think it would be a shame to lose field of view, especially since the chip is pretty small anyway. We just use two identical cameras, as Rob suggests. Sometimes we run RGB, RGB on one and BGR, BGR on the other if the clouds are threatening but mostly we do L on one and RGB on the other. One has Ha and the other OIII as well.

You'll want a software capable of resizing and co-registering. I use Registar and love it, but I think APP can do it and maybe Pixinsight, if you can fathom it!

 

Olly

Edited by ollypenrice
I misread 412E and was thinking of the 320E.

Share this post


Link to post
Share on other sites

Hi Olly,

I suppose with much smaller identical scopes and lower resolution this wouldn't be such a big issue. But finding a rigid enough adjustable plate to hold a TEC140 + associated weight is a different animal. I could not eliminate DF over 5 min at a resolution of around 1 arc-sec on both scopes (until I used AO...at which point I could pretty much go unlimited).

How do you dither? Do you synchronise your cameras?

Peter

Share this post


Link to post
Share on other sites
10 hours ago, prejto said:

Hi Olly,

I suppose with much smaller identical scopes and lower resolution this wouldn't be such a big issue. But finding a rigid enough adjustable plate to hold a TEC140 + associated weight is a different animal. I could not eliminate DF over 5 min at a resolution of around 1 arc-sec on both scopes (until I used AO...at which point I could pretty much go unlimited).

How do you dither? Do you synchronise your cameras?

Peter

A friend and I are considering mounting our TEC140s in dual rig mode at 0.9"PP resolution. This will be the acid test if we try it. The Cassady device is a really meaty item though, and very well thought out.

CASSADY%20PAN-M.jpg

CASSADY%20TILT-M.jpg

We were dead lucky that another friend spotted this one for sale second hand. It still cost a fortune but it is superbly effective.

We don't dither. The enormous amount of data we collect seems to make up for it.

Olly

  • Like 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Recently Browsing   0 members

    No registered users viewing this page.

×

Important Information

By using this site, you agree to our Terms of Use.