SGPro, CGEM, PHD2, and Stellarium


This has been gone over before in other threads, but there is a new twist.

I can connect SGPro, and PHD2 to the CGEM using the Celestron Telescope ASCOM driver. I can also use the POTH ASCOM (which is a bit tricker to set up).

But regardless of which ASCOM driver I connect with, I have to disconnect both of them in order to connect Stellarium (to do a GoTo) to the same driver. Then I have to disconnect Stellarium (after a GoTo) and reconnect both PHD2 and SGPro.

The only options for connecting to the mount in Stellarium are “directly through a serial port” or via an “external software or a remote computer.” I can make the connect directly, but I don’t know the connection information to use the external software. The connection settings are Host (localhost - default) and TCP port (10001 - default).

I figure the best place to start is here because someone here in the SGPro forum might know what the Stellarium connection settings should be.

Now if I could use TheSkyX Serious Astronomer Edition instead, that would be cool, too. But again, setting up the mount and everything is confusing to me. I tried both POTH and Generic HUB, but TheSkyX rejects them.


John C.


I have found the internal scope controls in Stellarium to be flaky at best
and difficult to manage. I use Stellariumscope to connect between
Stellarium and my mounts. Give that a try.


Hi John,

I don’t have the same mount but I DO use The Sky X (SAE) to control my Tak mount sometimes. I do not have to turn off SGP or PHD 2 to use the SkyX to slew the mount…I can switch between the different programs without problem and the mount control is available to each program as required. This was not always the case for me and I believe it was ‘fixed’ when I chose the correct driver in The Sky X (…in truth I can’t honestly remember though).

To the best of my knowledge though each program controlling the mount should use the Ascom driver…this is a snip from the Sky X (SAE)… (for me of course I choose the Takahashi ASCOM driver…you would choose diferent)


I seem to recollect that if the programs have different User Account settings (I.e. administrator on one, not on the others) then Windows won’t let them connect together. This is a vague memory trace of how I fixed my problem a while back. Someone more knowledgeable could help here.


Hi JohnC
Use generic hub instead of POTH :slight_smile:


The reason that you can’t use the internal Stellarium control at the same time as ASCOM is because both the Stellarium control and the ASCOM driver need exclusive access to the serial port that’s connected to the scope. You need everything to use ASCOM, maybe through a hub if the driver doesn’t support multiple connections.

AIUI StellariumScope uses ASCOM.



What I found that works is to use Starry Night Pro Plus 7 in Windows 10 to control the mount. Giving it full access to the Celestron driver (instead of the Generic Hub) allows it to be fully synchronized with the mount. Sequence Generator Pro then needs to be connected via Generic Hub and configured to allow an external software to control the mount, but that’s only if I want SGP to perform a sequence of tasks (centering, focusing, imaging).

For what I use this telescope for (public outreach), I don’t mind not having to do precise centering or automatic focusing. Hence, just about any software that can access the mount will do.

John C