Re: Dual scope setup question

Emilio J. Robau, P.E.

I guess running one at a time would be okay, but what is the sense?   With the cheap Chinese cameras you could get lucky and get a good camera and run both cameras at one time.  Why not?


NINA, SGP, APT, and Voyager can deal with multiple instances with no issues.  I have run the QHY 294 and a ASI 1600 along with a Moravian 16200 with no issues.  I have run all the aforementioned applications with an array.   I ran the 294 in 1 bin mode and it produced 92 meg subs.   That is the largest size sub I have encountered.  No issues.


The main issue is coordinated dithering.  APT can’t focus embedded in a sequence so that one is not very useful due to that lack of functionality.


From: [] On Behalf Of Christopher Erickson
Sent: Friday, May 14, 2021 3:09 PM
Subject: Re: [ap-gto] Dual scope setup question


If you are only running one at a time, having a NUC for each cam and OTA works fine.


In fact I don't know of any capturing software that can handle two big cams at once and be able to handle automated scheduling.

-Christopher Erickson
Observatory engineer
Waikoloa, HI 96738


On Fri, May 14, 2021, 4:45 AM Emilio J. Robau, P.E. <ejr@...> wrote:

I run three scopes on one AP1600 mount with one computer.   I don’t know how you would get coordinated dithering if you place a computer on each scope and think that having multiple computers on one mount is not the solution.   The only challenge I have besides and occasional flexure of one of the scopes which misaligns it is coordinated dithering.  I just trash a sub or two when dithering interferes.   NINA has coordinated dithering, but I have not tried it yet.  I find it somewhat efficient to just lose a sub or two due to dithering.






I never thought about this, it is a great idea to use 2 computers to make two systems independent. 




On Wed, May 12, 2021 at 11:44 PM Christopher Erickson <christopher.k.erickson@...> wrote:

Personally if I were doing a dual scope setup on one mount I would put a NUC on top of each OTA and have two serial cords going down to the two serial ports on the CP3/4/5. SO MUCH EASIER to get the software bits to all work correctly when each NUC only sees one cam, one filter wheel, one mount, one focuser, one autoguider, etc.


Or MUCH BETTER yet, give each OTA it's own AP mount.


And just like I always say...

"My advice is free and worth every penny!"


-Christopher Erickson

Observatory Engineer

Summit Kinetics

Waikoloa, Hawaii





On Wed, May 12, 2021 at 6:02 PM Kent Kirkley via <> wrote:

If each gas it's own OAG, no problem.

I can't advise on 'wiring' as I use an AP1200 which doesn't have
thru the mount access. I would say just minimize and carefully
route the cables, bundle and cord wrap.

Kent Kirkley




-----Original Message-----
From: yanzhe liu <liuyanzhe@...>
Sent: Wed, May 12, 2021 7:16 pm
Subject: Re: [ap-gto] Dual scope setup question

Yes, Imaging.


When you say both can work, are you talking about "piggy back" and "side by side"?

How about power supply and USB?


Each will have its own OAG to eliminate flexure.




On Wed, May 12, 2021 at 2:09 PM Kent Kirkley via <> wrote:

By 'one at a time", are you referring to imaging?
Either way can work, I've done both.
The biggest issue will be the possibility of flexure between
components depending on how you will be guiding.
If you intend to use an off axis guider on both scopes, no problem.
If you intend to use a guide scope of some sort, be wary of how it's
mounted. Scopes are usually mounted in rings which have felt, cork or
some other material lining them. If a guide scope is mounted on the rings,
the main scope can move slightly within the rings which the guider won't

know about. The result, oval or trailed stars.


To prevent this, mount the guide scope directly on the primary instrument, not
on the rings.
This also applies to a side by side set up where you mount the guide scope
on the side by side plate.

Kent Kirkley




-----Original Message-----
From: yanzhe liu <liuyanzhe@...>
Sent: Wed, May 12, 2021 3:53 pm
Subject: [ap-gto] Dual scope setup question

Have been thinking of setting up two scopes (4" and 5") on AP1100, only 1 scope will be used at any time.

A few questions on exactly how it should be configured/connected.

- Piggy back vs side by side? Which is the preferred way.

- I am thinking of having 3 110v/12V power adapters, and 3 USB ports.

One power adapter and one USB port are for connecting GTOCP3.

Each telescope will have a power adapter and a USB port, which provide power and communication for all gears eg, CCD/focuser/dew controller/USB hub etc.


I am not too sure whether there are any potential issues with this setup:

- Can all 4 cables (2 powers and 2 USB2 cables) go through AP1100?

- Is there any concern on the electrical side, e.g. USB ground loop or something similar?

- Or is it possible to have 2 scopes sharing the same power and USB? Then I need a IP controller 12v power switch?





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