I recently set up a 13 metre umbilical to connect my “GOTO” ETX 80 scope placed on my lawn with my Laptop PC located inside the Control Room to allow remote control and image capture.
Click on an image to see a larger view.
Meade ETX 80 tracking Mars via AudioStar controller on the morning of 14 September 2020 with imaging via QHY5 camera to Laptop (both AudioStar and QHY camera connected to PC in Control Room via 10 metre active USB cables)
The umbilical cable consist of two 10 metre active USB extensions and a mains powered DC power supply which can quickly connect to Laptop, scope and a QHY5 camera, to allow “armchair” operations with both computer equipment and observer being shielded from the outside conditions inside the Control Room.
Control Room view of Laptop and second monitor selecting scope targets and capturing images. Adjacent iPad connected as a third wireless monitor
The setup works well when using Meade’s “Auto Star Suite Astronomers Edition” software to adjust guiding and selecting targets for the scope and “EZPlanetary” image capture software to record data from the QHY camera.
The shortfall however comes when needing to be able to correctly focus the camera in the absence of a remote controlled focuser. Although I have successfully installed stepper motors on some of my scopes which allow remote control focusing via an infrared remote control, the nature of the Meade ETX 80 focusing system prohibits the use of this particular method of focusing, so focusing has to be done at the telescope itself using the manual focusing knob. In order to be able to “see” what the camera (and the Laptop in the Control Room) is looking at locally at the telescope therefore, I needed a simple way of doing this.
Whilst its possible to “cast” certain tablets and phones to Laptops using “Airplay” and “Screen Mirroring” techniques, doing this the other way round is not as easy. In exploring how best to do this however, I found a far simpler workaround which allows an iPad to be used as a wireless monitor for my Laptop via an app called “SpaceDesk”. This basically allows the iPad to act as a second or third monitor for your PC, Mac or Laptop, free of any cables, allowing it to be taken anywhere within range of the WiFi signal. It is then possible to clone, duplicate or extend the desktop showing the camera capture image to the iPad which can then be taken to the scope (provided it is in range of the WIFI signal) to allow fine focusing at the telescope itself. The iPad can then be taken anywhere in range of the WiFi to keep an eye on how capturing is going.
Set up of “Space Desk” is very straightforward and is available as a free download. It requires some software to be installed on both computer and tablet to make it work which can be downloaded from https://spacedesk.net/ where further details of how this works can be reviewed. Although I have used this for wireless operation it is also possible to use tethering via USB and it can also exploit LAN as well as wireless internet.
It will be good to be able to demonstrate this set up at future outreach events and even carry out live-streaming via Zoom in the future. With the help of Nik Whitehead I am currently exploring whether this might be possible using an iPad on a 4G connection to stream views from Fairwood’s 12” Meade for special live-streaming events on Zoom.
Montage of complete setup showing iPad in use as a wireless monitor displaying camera output.
Chris Bowden
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