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Remote Control

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Bullet Remote Monitoring / Remote Control
Bullet Remote Control (Clair Observatory), 2012+
Bullet Remote Control (Clair Observatory), 2004-2011
Bullet Remote Control (Kingcup Observatory), 2002-2003

 


Remote Monitoring / Remote Control

I use remote control for monitoring the status of automated image queue, addition/insertion of new targets into the job queue, monitoring sky conditions/image quality with any consequential re-prioristiation of targets in the job queue .   Since the remote control is over the entire laptop  (not just a particular package) it allows any function or program to operated on the observatory laptop exactly as if I was sitting in the observatory myself. 

A key requirement before leaving the observatory and retreating inside is to ensure that RealVNC Server is live on the laptop and the IP address has been noted (it can occasionally change if laptop hasn't been used for a few days)

It took a number of years before Remote Control technique was perfected. Earlier attempts (pre-2006) had used NetMeeting and/or Remote Assistance and where less satisfactory.

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Remote Control (Clair Observatory), 2012+

The Clair Observatory is now setup to permit remote control of the telescope and imaging from inside my house using a Power-Line networking connection. The setup from Oct 2012 onwards is 

From 2004 to mid 2012 I used a wireless (WI-FI) connection to the house's LAN network.  This provided sufficiently good connection up until Feb 2009, when I upgraded to a larger scope and built a new run off roof, afterwhich I began to get increased problems from lost connectivity during remote operation. This required making unwanted trips out to the observatory to restart the wireless connection, but in some cases the connection couldn't be restored without rebooting the laptop.   This made remote control somewhat frustrating and has been one factor in reducing my use of the observatory in 2011-2012.  Trying alternative WIFI settings & channels, an alternative VNC product (UltraVNC)  and alternative VNC parameters hasn't really improved the situation, and it is assumed that the problem is somehow associated with the much larger telescope/ metal work and possibly the rolled off roof lying between house and observatory  but might potentially be compounded by an increasing number of neighboring Wifi networks. Hardware lockups on the laptop during intensive image downloading haven't been ruled out as a factor.

Frustration with Wireless Connection dropout became so bad in 2012 that I began to consider other options for gaining a computer connection between observatory and house.  Retrofitting a wired ethernet cable between observatory and household router was considered but quickly dropped to bottom of the list due to relative difficulty of retrofitting a cable to the observatory and to household router indoors.   The use of Power-line networking to extend the household LAN across the existing household power circuit and power cable to the observatory was a much more appealing idea, but initial lack of knowledge about this technology and concerns about impact of electrical interference and CCD image quality and the use of extensions cables and intervening residual current device (RSD) stopped me from pursuing this for sometime. 

Finally (Oct 2012) I took the plunge and bought a pair of TP-Link AV200 Mini Multi-Streaming Powerline Adapters (TL-PA211) online for a cost of 32. The pair of adapters are easily twinned via a 'Pair' Button and data communication’s security is achieved by built-in 128-bit AES encryption. One Powerline Adapter was installed in an observatory power socket with an Ethernet cable connected to Laptop with another Powerline Adapter installed in a socket indoors with Ethernet cable connected  to the household router. Initial tests appear promising with transmission rates of 100-110 Mbps (compared against the advertised 200 Mbps rate for the equipment), no visible impact to Flat & Dark Frames when data is being transmitted and good/acceptable VNC connectivity to the house computer. The limiting factor on overall transmission becomes the wireless transmission rate between the router and house computer, which could theoretically be raised by means of an additional Powerline adapter and the processing priority of the VNC server on the observatory laptop.

Remote Access Software, 2012+ (UltraVNC)
Following problems with regular lose of connection between Observatory and House computers I began exploring other remote access software desperate for something that might solve or ease the problems encountered.  I eventually came across a product called UltraVNC in Dec 2011 which looked quite good and seemed to work well when trialled.  One nice feature of the UltraVNC is that the Viewer that can be started in Listening Mode, meaning that remote connection between the House Computer and the Observatory can be made before leaving the observatory - assuming that the House Computer has been switched on first !.    (UltraVNC is compatible with RealVNC and other VNC variants. Some initial trials I made showed that communications successfully worked with RealVnc running on one computer and UltraVNC running on the other). 

Although the problems with connection drop-out continued the general performance of UltraVNC has made it my VNC program of choice. It is hoped that the use of Powerline Networking usng TP-Link adapters will solve the connection drop-out issue and allow remote control to be fully used again.

The two alternative procedures that I expect to use is as follows depending on whether the House Computer or Observatory Laptop are started first.

A) Observatory Laptop On first

  1. Start Observatory Laptop (laptop automatically connects to the LAN once Ethernet cable is connected with the Observatory Power on)

  2. Start UltraVNC Server. Note IP address (checking that is one of the expected numbers)

  3. Go inside House, turn on House Computer 
    (computer automatically connects to the LAN via wifi and starts up UltraVNC viewer, listening mode)

  4. Open VNC Viewer.  Enter IP address of Observatory Laptop. Enter VNC password
    (if IP address hasn't been noted, then run 'NetResView' to find required IP address)

  5. Operate Observatory Laptop remotely. Set remote window to Full Screen. 

B) House Computer On first

  1. Turn on House Computer. Note IP address (checking that is one of the expected numbers)
    (computer automatically connects to the LAN via wifi and starts up UltraVNC viewer, listening mode)

  2. Go outside.  Start Observatory Laptop (laptop automatically connects to the LAN once Ethernet cable is connected with the Observatory Power on)

  3. Start Ultra VNC Server.  Add New Client. Enter IP address of House Computer. Enter VNC password
    (if IP address hasn't been noted, then run 'NetResView' to find required IP address)

  4. Go inside House. Operate Observatory Laptop remotely. Set remote window to Full Screen. 

Provided connectivity is working ok and various versions of windows cooperate a potential useful application is NetResView (from www.nirsoft.net ) which lists the names and IP addresses of all the computers active on the local network.  This is handy if it was forgotten to take note of the IP address of the required computer.  

UltraVNC Product Link:   www.uvnc.com/ 

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Remote Control (Clair Observatory), 2004-2011

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 between 2004 and 2011 comprised.

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 control operation worked well through 2006-2008, but Wifi connectivity issues started appearing with dropped connections and dropped/frozen VNC connections. This is thought to be related to installation of a larger telescope with much more metalwork and a new roll-off roof, but might potentially be compounded by an increasing number of neighboring Wifi networks. Hardware lockups on the laptop during intensive image downloading haven't been ruled out as a factor.

Remote Access Software, 2006-2011
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 generally used 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 use 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.

Initial Teething problems in remote control of the Kingcup Observatory and solutions are listed below

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This Web Page: Remote Control
Last Updated : 2015-05-16
Site Owner : David Richards
Home Page : David's Astronomy Web Site