Dual scope setup question


yanzhe liu
 

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?

Yanzhe



Kent Kirkley
 

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@...>
To: main@ap-gto.groups.io
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?

Yanzhe



Bruce Donzanti
 

I have an 80mm piggybacked on top of my C11" on my AP1100.  Cameras on both with filter wheels and auto-focusers 7 USB ports.  I use to guide the 80mm with the OAG on the C11 and that works most of the time.  However, during windy nights it could struggle so I placed a second OAG on the 80mm and it works fine all of the time.  


Worsel
 

Yanzhe

There was a short thread on the dual scope topic back in March.  In fact, it was specific to the 1100, so you may find useful info at
https://ap-gto.groups.io/g/main/topic/81188350#76876

Bryan


yanzhe liu
 

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.

Yanzhe

On Wed, May 12, 2021 at 2:09 PM Kent Kirkley via groups.io <kgkirkley=aol.com@groups.io> 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@...>
To: main@ap-gto.groups.io
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?

Yanzhe



yanzhe liu
 

Thanks, I'll check it out

Yanzhe

On Wed, May 12, 2021 at 2:18 PM Worsel via groups.io <bryancashion=yahoo.com@groups.io> wrote:
Yanzhe

There was a short thread on the dual scope topic back in March.  In fact, it was specific to the 1100, so you may find useful info at
https://ap-gto.groups.io/g/main/topic/81188350#76876

Bryan


yanzhe liu
 

How do you power and access two CCDs? I dont want to power both since I will use one at a time.

Yanzhe

On Wed, May 12, 2021 at 2:16 PM Bruce Donzanti <donza2735@...> wrote:
I have an 80mm piggybacked on top of my C11" on my AP1100.  Cameras on both with filter wheels and auto-focusers 7 USB ports.  I use to guide the 80mm with the OAG on the C11 and that works most of the time.  However, during windy nights it could struggle so I placed a second OAG on the 80mm and it works fine all of the time.  


drgert1
 

An SBIG AO system on one of the OTAs will make it independent of guide moves of the other. As long as the flexure doesn't exceed the excursion range of the AO it will be fine.

Cheers,
Gert


Bruce Donzanti
 

I am in a permanent setup in an observatory.  Power comes from my house up to the observatory to a 110/120VAC to 12 vdc, 25A power supply which runs up to the GTOCP4 control box and the scope where I have a powered USB hub and a Linx Power Panel with 6 Anderson Power Pole Connectors.   While they are both powered at the same time, I seldom would use both simultaneously.   

On Wed, May 12, 2021 at 8:18 PM yanzhe liu <liuyanzhe@...> wrote:
How do you power and access two CCDs? I dont want to power both since I will use one at a time.

Yanzhe

On Wed, May 12, 2021 at 2:16 PM Bruce Donzanti <donza2735@...> wrote:
I have an 80mm piggybacked on top of my C11" on my AP1100.  Cameras on both with filter wheels and auto-focusers 7 USB ports.  I use to guide the 80mm with the OAG on the C11 and that works most of the time.  However, during windy nights it could struggle so I placed a second OAG on the 80mm and it works fine all of the time.  


Kent Kirkley
 

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@...>
To: main@ap-gto.groups.io
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.

Yanzhe

On Wed, May 12, 2021 at 2:09 PM Kent Kirkley via groups.io <kgkirkley=aol.com@groups.io> 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@...>
To: main@ap-gto.groups.io
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?

Yanzhe



Frank Widmann
 

Here is my AP1600 quad scope rig.
One 250 mm RC scope
One 152 mm refractor
Two 80 mm guide scopes.
Two through the mount power lines each feeding a ten-port Rigrunner power distribution unit.
One through the mount power line from a separate power supply for the anti-dew system.
Two through the mount USB cables each feeding a seven-port Startech powered USB hub.
I also added a USB controlled relay box on the mount to allow me to power cycle old school USB cameras and filter wheels.
The mount has its own power supply and is connected with an old reliable RS 232 line.
All of the off mount equipment is housed in a waterproof cabinet, and AC power is controlled with a WiFi DataLoggers switching unit.
All acquisition software, including APCC, SkyX, PHD2, Focus Lynx Commander, SGP, PEM Pro and MaximDL runs on a Kingdel industrial computer. There is a field monitor in the cabinet, but normally the Kingdel runs headless and is controlled from various computers using Remote Desktop.
With the help of APPM, I have no difficulty getting round stars with eccentricity of .5 or less, as measured by PixInsight, in either of the main scopes using either of the guide scopes.
I regularly image with both scopes, one camera shooting automated sequences controlled by SGP and one controlled manually with SkyX to work around dithering.
A key to successful side by side operation is to only use the best saddles, rails and side by side bars. No el cheapo. The target is visible in my main and guide cameras.
It takes careful balance to make it all work, and avoid off center loads.


Christopher Erickson
 

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


Virus-free. www.avg.com


On Wed, May 12, 2021 at 6:02 PM Kent Kirkley via groups.io <kgkirkley=aol.com@groups.io> 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@...>
To: main@ap-gto.groups.io
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.

Yanzhe

On Wed, May 12, 2021 at 2:09 PM Kent Kirkley via groups.io <kgkirkley=aol.com@groups.io> 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@...>
To: main@ap-gto.groups.io
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?

Yanzhe



R Botero
 

Yanzhe

I have been imaging with a dual scope rig on my 1100GTO (and now on a 1600GTO) for the last 12 months.  I mount my scopes side by side: a 6" f/7.5 StarFire EDF and a Stowaway.  In fact, the Stowaway's rings are attached via a small dovetail to the hexagonal rings (original AP version) of the larger refractor.  This keeps both scopes close together, their centre of gravity as near the DEC head as possible.  Aligning the smaller scope to the larger one just needed a couple of shims and the rig is as stable at all angles as I could wish.  I can take up to 10 min unguided exposures with the larger refractor (1.4"/px at 1300mm) in this arrangement (using APCC/APPM) without any trailing in any of the two imaging cameras.
I run all my cables through the mount:  two power cables, one for each CCD camera, two ethernet cables for the focusers, four USB cables - two for each camera, one for the main scope's filter wheel and one for the guide camera and finally three cables for dew heaters: one for each scope and one for the guidescope (AP's Baader Vario Finder).  I really should have run fewer cables through the mount and have a hub on top of one of the scopes but this is a historic build up of machinery...
My scope and cameras are controlled by Voyager Array which does the imaging, controls dithering and sequencing and manages my ROR.
See some pictures here:

https://www.astrobin.com/zwq72j/G/?nc=user


Good luck!

Roberto


Andrew J
 

On Wed, May 12, 2021 at 02:09 PM, Kent Kirkley wrote:
To prevent this, mount the guide scope directly on the primary instrument, not
on the rings.
Hi Kent/All.
 
Thank you for your response to the OP question. Your response reminded me of a question I have had for some time. I often hear the advice to avoid mounting a Guide Scope using rings and to mount the guide scope directly to the primary instrument to avoid flexure issues. What is not as clear to me is how to mount a guide scope other than small finder scopes to the primary instrument without using rings? 
I have a TEC 140 equipped with a Starlight Instruments FTF#3545 Feather Touch Focuser which has mounting holes for a small guide/finder scope. I currently use the 10×60 Baader Vario scope with the AP 10 x 60 Quick Release Guider Bracket (1060VGKIT). Which is all well and good as long as I stick with a small light weight finder/guide scope like the 10 x 60 Baader Vario scope. However, if I wanted to use something larger, like an 80mm scope for guiding, how can this be mounted directly to the primary instrument without using rings? I have just always been curious as to what mounting options you have if you want to use a larger guide scope and still avoid using rings. It maybe that the side-by-side mounting option being discussed in this thread is the only option, but just wanted to confirm. 

Thanks for the useful advice.
 
Clear Skies,
Andrew J


Kent Kirkley
 

Andrew

Contrary to rational thinking, you don't have to use a long focal length guide scope (depending
on the focal length of the imaging instrument).
I have an AP160 on an AP1200GTO mount and have used an SBIG eFinder with Remote Guide
Head with my SBIG STL-11000 camera. The Remote Guide Head and eFinder is mounted directly
to the AP160's focuser housing. It has guided the 1200mm focal length perfectly. Yes it's older technology
today but demonstrates long focal length guide scopes aren't necessary.
You could use any guide type camera and short focal length lens, even a 35mm camera lens or Borg
short focal length scope. Small and light weight is the key.

Kent



-----Original Message-----
From: Andrew Jones <andjones132@...>
To: main@ap-gto.groups.io
Sent: Thu, May 13, 2021 9:02 am
Subject: Re: [ap-gto] Dual scope setup question

On Wed, May 12, 2021 at 02:09 PM, Kent Kirkley wrote:
To prevent this, mount the guide scope directly on the primary instrument, not
on the rings.
Hi Kent/All.
 
Thank you for your response to the OP question. Your response reminded me of a question I have had for some time. I often hear the advice to avoid mounting a Guide Scope using rings and to mount the guide scope directly to the primary instrument to avoid flexure issues. What is not as clear to me is how to mount a guide scope other than small finder scopes to the primary instrument without using rings? 
I have a TEC 140 equipped with a Starlight Instruments FTF#3545 Feather Touch Focuser which has mounting holes for a small guide/finder scope. I currently use the 10×60 Baader Vario scope with the AP 10 x 60 Quick Release Guider Bracket (1060VGKIT). Which is all well and good as long as I stick with a small light weight finder/guide scope like the 10 x 60 Baader Vario scope. However, if I wanted to use something larger, like an 80mm scope for guiding, how can this be mounted directly to the primary instrument without using rings? I have just always been curious as to what mounting options you have if you want to use a larger guide scope and still avoid using rings. It maybe that the side-by-side mounting option being discussed in this thread is the only option, but just wanted to confirm. 

Thanks for the useful advice.
 
Clear Skies,
Andrew J


Mike Dodd
 

On 5/13/2021 12:43 PM, Kent Kirkley via groups.io wrote:
...long focal length guide scopes aren't necessary.
You could use any guide type camera and short focal length lens, even a
35mm camera lens or Borg short focal length scope. Small and light weight
is the key.
I use a 60mm f/5 scope for guiding, with an old SBIG ST-402 camera.

Regarding small and lightweight guide scopes, years ago Chris Peterson (Cloudbait Observatory <https://www.cloudbait.com/>) sent me a photo of his guide scope.

Chris clamped a bare 80mm f/5 lens and the guide camera to a dovetail plate atop his SCT, with nothing in-between. The camera had a 1-1/4" nosepiece with a clear filter to prevent dew. He took minimalist to the extreme!

--- Mike


yanzhe liu
 

Great to know, since I use SBIG CCDs, I will keep that in mind.


On Wed, May 12, 2021 at 5:42 PM drgert1 via groups.io <drgert1=yahoo.com@groups.io> wrote:
An SBIG AO system on one of the OTAs will make it independent of guide moves of the other. As long as the flexure doesn't exceed the excursion range of the AO it will be fine.

Cheers,
Gert


yanzhe liu
 

I dont want to power up both CCDs, because I am not sure it will reduce the life significantly.


On Wed, May 12, 2021 at 6:24 PM Bruce Donzanti <donza2735@...> wrote:
I am in a permanent setup in an observatory.  Power comes from my house up to the observatory to a 110/120VAC to 12 vdc, 25A power supply which runs up to the GTOCP4 control box and the scope where I have a powered USB hub and a Linx Power Panel with 6 Anderson Power Pole Connectors.   While they are both powered at the same time, I seldom would use both simultaneously.   

On Wed, May 12, 2021 at 8:18 PM yanzhe liu <liuyanzhe@...> wrote:
How do you power and access two CCDs? I dont want to power both since I will use one at a time.

Yanzhe

On Wed, May 12, 2021 at 2:16 PM Bruce Donzanti <donza2735@...> wrote:
I have an 80mm piggybacked on top of my C11" on my AP1100.  Cameras on both with filter wheels and auto-focusers 7 USB ports.  I use to guide the 80mm with the OAG on the C11 and that works most of the time.  However, during windy nights it could struggle so I placed a second OAG on the 80mm and it works fine all of the time.  


yanzhe liu
 

Chris,

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

Yanzhe

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


Virus-free. www.avg.com

On Wed, May 12, 2021 at 6:02 PM Kent Kirkley via groups.io <kgkirkley=aol.com@groups.io> 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@...>
To: main@ap-gto.groups.io
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.

Yanzhe

On Wed, May 12, 2021 at 2:09 PM Kent Kirkley via groups.io <kgkirkley=aol.com@groups.io> 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@...>
To: main@ap-gto.groups.io
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?

Yanzhe



yanzhe liu
 

It is amazing that you can run so many cables through 1100, make your scopes look so clean.


On Thu, May 13, 2021 at 1:12 AM R Botero via groups.io <rbotero=sky.com@groups.io> wrote:
Yanzhe

I have been imaging with a dual scope rig on my 1100GTO (and now on a 1600GTO) for the last 12 months.  I mount my scopes side by side: a 6" f/7.5 StarFire EDF and a Stowaway.  In fact, the Stowaway's rings are attached via a small dovetail to the hexagonal rings (original AP version) of the larger refractor.  This keeps both scopes close together, their centre of gravity as near the DEC head as possible.  Aligning the smaller scope to the larger one just needed a couple of shims and the rig is as stable at all angles as I could wish.  I can take up to 10 min unguided exposures with the larger refractor (1.4"/px at 1300mm) in this arrangement (using APCC/APPM) without any trailing in any of the two imaging cameras.
I run all my cables through the mount:  two power cables, one for each CCD camera, two ethernet cables for the focusers, four USB cables - two for each camera, one for the main scope's filter wheel and one for the guide camera and finally three cables for dew heaters: one for each scope and one for the guidescope (AP's Baader Vario Finder).  I really should have run fewer cables through the mount and have a hub on top of one of the scopes but this is a historic build up of machinery...
My scope and cameras are controlled by Voyager Array which does the imaging, controls dithering and sequencing and manages my ROR.
See some pictures here:

https://www.astrobin.com/zwq72j/G/?nc=user


Good luck!

Roberto