Tech – First Hardware/Software Test

As mentioned in previous posts, the telescope for the KRO already exists. It is located in a observatory north of Linz, quite easily accessible for us. So we can test most of the modernized functions already there.

What was the goal of the first test:

• controlling the telescope with the SiTech Servo II
• testing the myFocuserPro2 (a DIY motor focuser)vand the autofocus mode
• testing if all works with Astroart (image capturing, filter wheel control, auto focus control and telescope control for fine adjustments
• using Stellarium (and StellariumScope) to find and GoTo to the desired Object (you can find a German document pointing out the usage of Stellarium with a telescope here, by Johannes Stübler
• Remote control (remote connection to the telescope server)
• test of the underlying ASCOM layer (ASCOM POTH)

First of all, the test went really well, all components worked together and we ended up needing just two programs to do the job of finding objects and take images of them. The underlying ASCOM, SiTech system doesn’t concern the user and therefore the user do not have to deal with the complex lower layers. Users only have to deal with Stellarium for finding the objects and pointing to them and of course the image capture software Astroart.

The test setup: in front the remote notebook PC from where we perform the observation, in the back the telescope server which is connected to the scope via SiTech controller and on the left side behind the notebook, the telescope itself. (Photo by Günther Truhlar, 18.09.2018)

The software is preconfigured and ready to use. So the first thing is to locate and GoTo the desired object. For this the we only have to open Stellarium and open the telescope dialog.

The telescope control and GoTo dialog in Stellarium. (Screenshot by Johannes Stübler, source)

Once the we hit “GoTo” (in the image above “Schwenken”) the telescope will point to the desired object and we now can switch to the image capturing tool.

The first step there is to focus the camera. For this Astroart supports an auto focus feature which is compatible with our ASCOM motor focus:

The autofocus dialog in Astroart. The small rectangle in the main image window shows the region or the star which Astroart should use to focus. You can see the star then also in the small focus window. (Screenshot by Günther Truhlar, 18.09.2018)

The test setup of the motor focus hardware. In front you can see the motor driver DRV8825 , on the left the rotary encoder for manual focus adjustment and in the back the display and the controlling Arduino Nano (right beside the display).And you can also see some sweets we brought with us for motivation 🙂 . (Photo by Günther Truhlar, 18.09.2018)

After a successful focus procedure, we only have to select the desired filter and trigger an image acquisition (either single mode or as predefined sequence or as predefined script).

Test image with M33 in the center and filter select dialog on the right. Currently the green filter is selected.  (Screenshot by Günther Truhlar, 60sec, 18.09.2018)

Another test image, in this case the bubble nebula NGC 7635, with the clear filter and 30sec exposure. (Screenshot by Günther Truhlar, 18.09.2018)

We demonstrated that the basic user interface and telescope controls are working quite well together and it is already now possible to control the scope fully by remote connection.

We plan a second test session, discussed in a future post, where we focus on the 16-point alignment to increase pointing accuracy, reading out PEC-Data (to be able to compare before/after absolute encoders) and enabling auto guiding via PHD2. Perhaps we can shoot the last pretty picture on the old telescope location.

Once the tests are completed, we will disassemble the telescope on its old observing site, rework it, add the additional absolute encoders and rebuild it at its new observing site on the “Hohe Dirn”.

 

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