Observatory & Equipment
The Dome
Roof Observatory
The observatory itself is located on the flat roof, which is accessible via an external staircase. It was erected directly on top of the flat roof membrane using a terrace structure and was weighted down. The foundation for the steel telescope column is mechanically decoupled and was anchored directly to the concrete ceiling.
Pulsar Observatory Dome (2.7m, Full Height)
Fully remote controllable Dome-Setup with slaved rotation drive and automated shutter. Safety Management is realized via Lunatico Astro`s AAG Cloudwatcher (rain, wind and cloud limits) and implemented via the sequencer software N.I.N.A. Humidity control, automated light, heating and indoor cameras enable fully remote operation.
Mount and Foundation
The Skywatcher EQ8-R mount is installed on a steel column, which in turn stands on a mechanically decoupled reinforced concrete foundation. With a load bearing capacity of 50 kg the EQ6-R is able to carry 2 OTAs.
I have tried to document the construction of the observatory accordingly:
Observatory Setup
Standard OTA (Newtonian)
The standard rig is a 10-inch Newtonian Telescope with a carbon-fibre tube operated most of the times in f/4 and a native focal length of 1,000 mm). It is fitted with a high-quality Astroreflect primary mirror and an Antares secondary mirror.
For widefield photography and visual observing a Lacerta 80/500 Apo-refractor is mounted on the rear top of the Newtonian.
Guiding is usually done with Lacerta`s MGen-3 and the use of a small refractor (Skywatcher Evoguide 50/242). A flat panel is installed to automate the calibration flat frames (RBFocus Excalibur).
Modified SCT Configuration for Long Focal Length Imaging
For applications requiring a longer focal length, a Celestron 9.25-inch Schmidt-Cassegrain optical system is used (native focal length 2,350 mm).
Due to initial problems with mirror shift during long exposures and meridian flip, I modified the Octoplus focuser – originally intended for a Newtonian telescope – and mounted it at the rear of the SCT. This allows the primary mirror (roughly pre-focused) to remain ‘locked’ in position at all times, whilst fine-tuning is carried out via the EAF (electronic autofocus) mounted on the Lacerta Octoplus focuser.
As can be seen in the photo, the SCT is operated using the ASIAIR system (also for mobile use). In the observatory, however, control must be carried out via N.I.N.A., as the observatory’s shutter also needs to be integrated accordingly, which is not yet possible in ASIAIR.
In future, two OTAs are to be operated in a dual setup, with the main telescope controlled via N.I.N.A. and the secondary optics via ASIAIR.
Cameras
Standard cam is the ASI 2600 MM Pro, a dedicated cooled astrocamera with a monochrome APS-C sized sensor. This cam is operated using a 2″ filterwheel with L,R,G,B broadband and narrowband filters (H-alpha, O-III and S-II, Optolong 3nm) and also a Rotator (ZWO`s CAA) to be able to adjust the image orientation. To measure any tilt in the Imagetrain, I have installed a dial gauge connected via the EFW.
Additionally a Sony Alph 7-IV is available for the Lacerta Apo or mobile use.