How To Drive My Telescope With My PC???

Shnoz (Sophie) · #1 15-05-2010, 02:23 PM

Hey I have a Skywatcher HEQ5 go-to telescope and I wanted to know how to drive it with my computer. Do I just need a planetarium program that will drive a telescope, or do I need other bits of programming as well? I have the program Stellarium at the moment, but I'm pretty sure it can't interact with my telescope.

Dennis · #2 15-05-2010, 03:32 PM

Hi Sophie

Your particular telescope mount is a physical instrument which has certain mechanical characteristics. Meade is different to Skywatcher, is different to Celestron, is different to Takahashi, is different to Vixen, etc.

A planetarium program is a software application that (in theory) can command a mount to perform certain functions, such as aligning on a star, doing a GoTo, finding a galaxy, etc. provided it can “understand” and “communicate” with the mount.

To do this successfully, most mounts come with a “Driver” from the manufacturer of the mount which defines and controls how the mount will behave when under the control of a planetarium program.

There are many telescope mount manufacturers and each has their own design. There are also several planetarium programs and each one of these has their own design and way in which it interacts with a physical mount.

To help standardise on the interface between mounts from various suppliers and software programs from various authors, there is an independent software “interface” called ASCOM.

It is my understanding that:

a) if the designer/manufacturer of a mount designs their mount with an ASCOM driver and provides this to you and,

b) the software author designs their planetarium program to operate in accordance with the ASCOM standards,

then in theory (provided you have the correct telescope interface cable) all you need to do is configure the planetarium software by selecting your telescope mount from a drop down list and perhaps set a few parameters and then you should be able to make a connection between your mount and the planetarium program and go from there.

Have a look at your mount manual to see if it mentions an ASCOM driver.

Cheers

Dennis

Shnoz (Sophie) · #3 15-05-2010, 04:29 PM

Thanks for your help, I didn't realise I needed a driver! But I think I may have come across another problem, I ran a program to detect activity in the COM ports and my computer's not detecting my telescope. The manual does say to have the telescope attached to the computer via a RS232 port and cable, but my computer doesn't have that kind of port, so I just joined the RS232 cable to a USB cable and plugged it in. Is there any way around the connection problem?

Dennis · #4 15-05-2010, 06:53 PM

Hi Sophie

My Notebook computer does not have a “native” RS232 connector, so I purchased a PCMCIA card that plugs into the card slot at the side of my Laptop and provides an RS232 (9 pin) connector on a dongle and this has always worked for me.

I had to configure the port for my Takahashi EM200 Mount per the attached file, but please note that this is specific to the Tak Temma mount and yours will be different.

I know that people on Ice In Space have had success with some USB to RS232 adapters, whereas other adapters have failed. I’m not sure which the good ones are – hopefully someone will chime in and name a particular brand/model.

In terms of the ASCOM Driver, I had to install a separate (3rd party) Driver for the Tak mount as Takahashi do not provide one, but you’ll have to read your mount manual to see what you need to do for the HEQ5. On my Vixen mount I think I had to set the Baud Rate as well as the Stop Bit to configure it for e.g. Starry Night Pro.

Cheers

Dennis

PS – PCMCIA is now old technology, the new (smaller) cards are called PCI cards I think?

Shnoz (Sophie) · #5 16-05-2010, 04:56 PM

I think I may have solved the communication problems between my computer and telescope now. I think I just needed a program that told my computer what cables I was using. (It works now!

)
But I'm having more luck communicating with the telescope with the serial telescope controller than the ASCOM controller. Does anyone know what the technical difference is? And if I'm using the serial controller do I just need a program that supports my telescope?

Barrykgerdes · #6 17-05-2010, 07:58 AM

If your telescope has a Go to facility ( even a manual push) and a port to connect to a computer you will be able to attach the scope to the computer. and drive it in some way, If it only has encoders you may only be able to display position on the computer

The port for a cable to connect to the computer will almost certainly be a RS232 port. That means it will need a cable either hand made or purchased to connect to the computers RS232 port. Most of the modern computers, particularly lap tops, these days do not have a RS232 port or PCMC1 slot so it will be necessary to use a USB to RS232 converter. The reason for perservering with RS232 for communication is most likely the limited distance that USB can be used over.

Most of the commercial planetarium programs have a computer control menu on which you can select the already installed drivers and immediately have control (or indication) of a telescope that has been aligned. For the programs that do not have a that driver installed the ASCOM interface can usually be used to add further drivers. The ASCOM driver is an external driver program that can recieve and send information to a telescope and computer if there is no existing controller.

Stellarium is a good free planetarium program that can be used on a limited number of telescopes directly but there is an ASCOM driver to suit the HEQ5. The full instructions for doing this are in an article in the Projects & Articles section I believe. There is also a program called Stellariumscope that can be used with Stellarium and ASCOM to give a much expanded menu of control features.

Barry

Shnoz (Sophie) · #7 17-05-2010, 05:14 PM

Yeah, I'm just using two cables to join my telescope and computer. One has the RS232 ends and the other has a RS232 and USB end. I think it works, I just need to test it out and see what happens.
And I've just found the article in the Projects and Articles section actually

, I'll take a good look there! Hopefully Stellarium will run alright with my HEQ5!

Shnoz (Sophie) · #8 07-07-2010, 01:09 PM

Mmkay, the holidays have given me loads of time to fix up my telescope, so I'm still trying to get it running with my computer

. And I've been looking through Karl's article, http://www.iceinspace.com.au/63-581-0-0-1-0.html but I've hit a snag.
When I get to 2.4 in the article, I hit the connect button and the screen almost comes up, but then it shuts down before it fully loads.
The only problem I can think of is the way I installed the EQMOD software. I only installed EQASCOM V121d, and I hope that was right???

Screwdriverone (Chris) · #9 15-07-2010, 10:55 PM

Hi Sophie,

I just bought an HEQ5 and have already got the PC link working well with Stellarium. You may not have the ascom driver selecting the proper com port for your USB to Serial port. Check that. I also found that the manual suggested the Celestron 5i and or the CPC GPS scopes, both of which DID NOT WORK, so I used EQAscom too.

Here's what I did to get it working. (omit any steps for software you have already downloaded.) You should have the scope pointed to the South Celestial Pole and powered up (you can do this inside and PRETEND its pointed there for testing).

1) First, you need to download and install the ASCOM driver to enable your laptop to know the language to talk to Ascom compliant mounts (such as the HEQ5). This is what I did and then downloaded the Celestron driver (you might be able to skip this step, now that I think of it) MAKE SURE YOU ALSO INSTALL THE UPDATE for the Ascom package.

2) You will need EQAscom downloaded and installed next. This will ADD the EQMOD eq5/eq6 driver to the list of scopes in the ASCOM section.

3) Download Stellariumscope from here and install it. This provides the interface to Stellarium to allow it to have a telescope connected to it. (looks like a scope on the bottom line)

4) On the Hand controller of the HEQ5, go to the UTILITY menu and select the option for DIRECT PC Control, the screen will confirm this and say "press ESC to cancel". (make sure you have the cable plugged into the second port on the HAND CONTROLLER - this is the serial to telephone plug type cable that came with the mount).

5) Run Stellarium scope and in the driver box at the top click on the ... box , select the EQAscom type eq5/eq6. Then next to this is a tick box, click it to try connecting to the scope. You should now hopefully be connected to the scope. This will show the EQMOD ascom driver on the screen and show you ready to go.

6) At the bottom of the stellariumscope window, press the UPDATE Stellarium configuration and then say yes to the choice buttons that come up. Tick the Auto start Stellarium button.

7) Now, you should hopefully be connected to the scope and you can use Stellariumscope ONLY to start with as this will automatically boot Stellarium up when you start it. Connect to the mount using the tick box and then flick back using Alt Tab to the Stellarium window and you should now have a SCOPE crosshair type target on the South Celestial Pole.

8) Once in Stellarium, with the cross hair up, click on a star and then press CTRL 1. This should make the HEQ5 slew to the star you picked. If you want to stop it on the way, you can press CTRL 5, to sync the scope again, press CTRL 3.

9) On the EQMOD driver page, there is a button on the bottom which allows you to park/unpark the scope and should tell you the current status of the scope, use this if nothing happens as the program may think the scope is parked and you need to unpark it to move it.

10) Hopefully this is all working for you, I apologise if something is missing in the instructions, I am writing this from memory as I did LOTS of things two nights ago to play with this and get it going, some of the things I did werent necessary so they cloud my memory of it somewhat.

I dont think you need to "learn" the scope or align it first, but I havent tried this yet as I only tested it outside for a little while last night and this was after I aligned it first.

Good luck, hopefully it works for you.

Edit: Damn, I just realised that this is almost exactly the same as Karl's article (which I read before I tried my one), but obviously mine is not as good. sorry.

Cheers

Chris

Shnoz (Sophie) · #10 16-07-2010, 04:48 PM

Thanks Chris! I don't have the direct PC control option in the utility menu of my hand controller, which is strange. The manual that my telescope came with definitely says that my telescope can connect to a PC though, so perhaps it's just later versions that have that option. And my computer does recognise that my telescope is connected. Other than that I have followed all of those steps, so I have quite a problem here!

I did manage to bypass the StellariumScope program and connect my telescope to Stellarium directly. But I can't give a stop command (easily) without shutting down the entire telescope.
So I reckon I'll try updating the version on my hand controller and see what happens (hasn't been updated in a while, so it might do some good!

)