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Computer Control

A laptop computer is used to operate my LX200 telescope and SBIG CCD camera.  

The laptop is connected to the telescope via a RS232 cable and a NewLink USB Serial Adapter. Control of the telescope is performed with Software Bisque's TheSky6 planetarium software package either directly or more usually indirectly via a self written Control Program called AIS.

The laptop is connected to the CCD Camera via Parallel Port/Parallel Cable. Control of the camera is performed with CCDSoft software package (Software Bisque)

Product Links:
TheSky:      www.bisque.com/Products/TheSky6
CCDSoft :  www.bisque.com/Products/CCDSoft/ 
NewLink :   www.newlinkproducts.co.uk/prodinfo.asp?catID=4&prodID=89 

Notes :
A Belkin Serial to USB Connector was formally used for used several years but it began to get intermittent, but annoying Driver related crashes in April 2006, which couldn't be resolved and was eventually replaced with a NewLink USB Serial Adapter in August 2006 ] 

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Remote Control (Clair Observatory), 2004-2006

The Clair Observatory is setup to permit remote control of the telescope and imaging from inside my house using a wireless LAN connection. The setup comprises 

• A laptop in the observatory, which connected to the telescope and CCD camera as described in the computer control section above.

• A 54g wireless connection with LAN (local area network) operating in house.

• A desktop computer or second laptop in the house. 

• Both computers operating Network software (TCP/IP) on Windows XP.

• Remote access software (see below)

Remote Control was not regularly used until Oct 2006. This was due to a number of reasons

- some difficulty/issues with previous remote access software
- access to automated imaging scripts, which removes some of the requirement to stay at the telescope in any case
- requirement for monitoring of outside cloud / dew conditions 
- house computer with lower screen resolution than the observatory laptop

During the 2006/2007 winter season remote control began to be used regularly after installation of RealVNC software which overcame some of the previous issues.

Remote Access Software, 2006

Following a tip from a reader of my website in Sept 2006, I downloaded and began using RealVNC software (Free Version, 4.1.2) in place of XP Remote Assistance/  Net Meeting Combination.  From initial testing it appears to be faster and more responsive and has the major advantage that access to the observatory laptop can be easily be initiated from the house computer, without 'manual acceptance'  or workaround previously used.   Like XP's Remote Assistance it allows Observatory Laptop Mouse/Keyboard to be used without disconnecting the connection.

Further tests in November/December 2006 over numerous sessions established that RealVNC was reliable/robust for practical use.

The procedure that I expect to use is as follows :

1. Setup Observatory Laptop (laptop automatically connects wirelessly  to the LAN)

2. Start VNC Server (User Mode). Note IP address

3. Go inside House, turn on House Computer (computer automatically connects to the LAN)

4. Start VNC Viewer.  Enter IP address of Observatory Laptop. Enter VNC password

5. Operate Observatory Laptop remotely. Set remote window to Full Screen / Use F8 to access RealVNC menu.

This is 6 steps shorter than the workflow method used in 2004-2005 (see below).

Notes:   Laptop set to 1280 X 1024 resolution, either beforehand or remotely (to be consistent with house computer)
Option exists to Start VNC Server (in Service Mode).

RealVNC Product Link:   www.realvnc.com

Remote Access Software, 2004-2005

Remote control of the observatory laptop during 2004-2005 was irregularly performed using Microsoft's Remote Assistance (with use of  Windows NetMeeting to help make the remote connection).

Initials attempts at using NetMeeting for remote control over wireless connection were disappointing, as video performance and windows control were found to be poorer & slower than ideal, and worse than when using a direct Cat5 connection as used in Kingcup Observatory. 

Experimentation with Remote Assistance (available with Windows XP) showed it to be much faster and have better video performance/more colours than NetMeeting. It also has the advantage that the connection doesn't have to be disconnected or the control released in order to operate the observatory laptop mouse/keyboard whilst making a visit to the observatory - with NetMeeting, control has to be released or link disconnected. 

However the  downside of Remote Assistance is that it requires a person to be in the observatory to first accept the request for remote assistance and then present again to accept a second request to take remote control.   This requires either two trips to and from observatory or the enlistment of a volunteer/family member to initiate the requests from the house.  If the connection is lost after family members have gone to bed a  double trip is indeed required.  With NetMeeting, this was not such a problem as the Observatory laptop could be set up to automatically accept remote connection.

A solution was found to get around the double-trip or family member assistance requirement when initiating a remote connection. This is to firstly use NetMeeting to make the Initial Remote Connection and then use it to remotely accept requests for Remote Assistance and Control.

The full procedure that I developed was as follows

1. From the Observatory Laptop open Remote Assistance and create an Invitation which is saved to a file (Advanced Option).  
   Note : I will typically set the invitation to have a password and have a 30 day duration before expiry (the maximum period).  It is best to create the invitation before the session starts and have the .msrcincident Invitation file already copied to the House Computer.
   [ an Invitation file can be used as many times as required with the Duration period ]
   

2. Setup Observatory Laptop and connect  to the LAN (wireless)
   Note : Ensure Accept Remote NetMeeting Connects is Turned On. It is also helpful to record the IP address being used (use ipconfig/all)
   

3. Go inside House, turn on House Computer and connect to LAN
   

4. Open NetMeeting and make a secure call to the Observatory Laptop
   (Note : you may need to use IP address to identify the Observatory Laptop and enter a username/password)
   Note : Remote Control should automatically be established if the setup is correct.
   

5. Click on .msrcincident Invitation file to call the Observatory Laptop.  Enter password if requested
   (Note : If the connection fails it may be that the IP address of Observatory Laptop has changed since original Invitation was created, could be the case when use ICHP on the LAN network..  In this case open the invitation file in a text editor (eg TextPad) and editor the IP address.)
   

6. Use NetMeeting window to remotely accept the request for assistance
   

7. Remote Assistance Window opens.  Click on Request  Control
   

8. Use NetMeeting Window to remotely accept the request for control.
   (Note :Remote Assistance Control is not still not achieved by this as the Meeting window still has overall control)
   

9. Use NetMeeting Window to kill the connection (Disconnect Remote Control)
   (Note : at this point Remote Control is handed to Remote Assistance Link)
   

10. Use Remote Assistance to set the Observatory Laptop to Accept Remote NetMeeting Connections
    (Note : we do this as it will allow a remote connection to be re-obtained should the Remote Assistance link be lost)
    

11. Operate the observatory, telescope / CCD Camera under remote control

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Remote Control (Kingcup Observatory)

The Kingcup Observatory was setup to permit remote control of the telescope and imaging from inside my house, though I didn't use this facility as much to date as planned. The following setup was used

- A laptop in the observatory, which connected to the telescope and CCD camera as described in the computer control section above.

- A Cat V LAN cable (100 MPS), which connected the observatory to the house

- A desktop computer in the house. 

Both computers operates Network software (TCP/IP & NetBUI) on Windows ME. Remote control of the laptop was performed using the software product Windows NetMeeting (version 3.01).  With just 2 computers in the network a length of cross-over Cat V cable and a couple of wall points is all that is required to connect up the observatory to the house - no Network Hub is required.  In my case the cable run is around 25m, but I understand that a cable run up to 200m long would work without additional hardware.

This form of remote control is considered optimal as it enables local control of the telescope & imaging to be performed in the observatory, to allow setup, visual observing and more complicated imaging (involving CCD head rotation or eyepiece projection changes etc) to be performed, yet permit the flexibility to enable long imaging sessions to be accomplished from inside on cold winter nights.  

I didn't really used remote control as much as I had hoped.  This was due to initial problems which I had with Laplink Gold, before I started using NetMeeting.  See Initial Teething Problems section below.  I then begun using Windows NetMeeting instead and remote control testing gave no problems so far.

Other things
I still used the Laplink Gold product to synchronize astronomical files between laptop and desktop computers. "Xchange Sync Agents" can be setup and stored for repeated later use, which is very handy as my 2 computers were not normally networked together and I tended to do work on both computers and therefore needed to keep information, images and webs in sync from time to time.  I preferred the control that Laplink Gold offered me, rather than the 'black box' form of control provided by Windows Synchronization.

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Initial Teething Problems

Initial Teething problems and solutions are listed below

• Problem :  Laptop making strange noises (humming) when connected to A/C Adapter cable. Power was supplied to the laptop via a 17m low voltage cable, with the A/C Adapter left in the house. (The same method had been used for several years to successfully operate the LX200 telescope - and I hopefully assumed that I could use the same method for operating the Laptop and ST7 Camera).
  Solution :  The problem was diagnosed to be an impact of loss of voltage along the cable connecting the adapter (in house) with the observatory. Laptop would run ok, but the voltage regulator for the TFT screen was being impacted by having less than the expected 18v input. Since the ST7 camera might also be susceptible to damage when operating at less than expected voltages  and has a more complicated power line cable it was decided to run a 240v power line out to the observatory, taking safety precautions such as a Residual Circuit Breaker (RCB) at the house end, armoured cable and 'weatherproof' sockets.  The laptop now operates normally.
  

• Problem :  A USB to Parallel Port & Serial Port Connector (manufactured by Belkin) was discovered to be unsuitable for CCD Imaging.
  Solution :  The Connector was originally purchased to provide a cheap docking facility for the laptop.  However reading the documentation in the pack made it clear than the connector did not have true 2-way parallel port operation, but was intended for simple (one-way) communication to a printer.   Since the laptop had a proper parallel port, but not a serial port, the connector was returned to the shop and a Belkin USB to Serial connector acquired instead.

• Problem :  Windows on remote computer freeze up when dragging or resizing windows whilst imaging using Laplink Gold. This was with Laplink Gold (version 3.2) and Windows ME on both machines. This problem necessitates closing down of the remote link and unplanned visits to the observatory to restart CCD Soft and Laplink Gold link or even to reboot laptop.  This was particularly frustrating and of course severely interrupted imaging tasks.

• Solution :  In the end I turned to using Windows NetMeeting (version 3.2) which was already installed on both machines.  This has a remote control operation and testing has so far shown no problems when imaging. 
  
  I was unable to find a workaround  involving Laplink Gold.  I tried unchecking the windows option 'Show Window Contents While Dragging'  and I tried not to resize or move windows whilst imaging. The former didn't work and the latter proved impractical.   

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