Observatory Code E17 (Leura) Long 150d 20' 30" Lat -33d 42' 22" Altitude 950m Time UT+10h
Observatory Code E19 ( Kingsgrove) Long 151d 5' 45" Lat -33d 56' 51" Altitude 60m Time: UT+10h
|
Observatory Code E17 (Leura) Long 150d 20' 30" Lat -33d 42' 22" Altitude 950m Time UT+10h Observatory Code E19 ( Kingsgrove) Long 151d 5' 45" Lat -33d 56' 51" Altitude 60m Time: UT+10h
|
|
| Leura Observatory instrument: Celestron Schmidt Cassegrain Telescope CGE 1400 (XLT) with Hyperstar option operating at f/11 with SBIG ST9XE at the visual end of the scope. The resultant image scale is 1.07"/pixel with a Field of View of 10' X 10'. The computer system consist of a P4 Dual core 3.2 G. Software utilizing the Sky 6 Professional, T-Point for planning and telescope control accurate to within a 10' Field of View using the combined system above. Also CCDSoft V5 for image acquisition and reduction using a library of Bias, Dark and Flat Field frames. Other software include The Orchestrate, NexRemote and PECTool for automation, remote control and improvement of guiding. Also a custom made Dome control software to control and synchronizes the movement of the dome with that of the telescope.
Due to the dark sky in Leura, when the sky transparency is exceptional , this setup is capable of detecting a 20 magnitude point source such as a star or an asteroid with an exposure of about 5 minutes. Kingsgrove Observatory instrument: Meade Schmidt Cassegrain Telescope the original LX series mounted on a modified Losmandy Gemini V3 GEM. The telescope is operating at f/5.2 due to an added variable focal reducer by Meade. Using this reducer it is possible to get to f/3.3 but this will severely compromise the image quality by introducing unacceptable aberration at the edge of the FoV. Attached to the visual end is an ST 402ME CCD camera used as an imaging camera. The resultant image scale when operating at f/5.2 is 1.41"/pixel with a Field of View of 18.1' X 11.9'. A 120 mm diameter f/5 achromatic refractor is piggy backed on the main telescope. This refractor is used with an SBIG ST-4 camera coupled with a flip mirror device as the system's autoguider. Usually when the imaging camera exposes longer than 2minutes, then the autoguider is required. The ST-4 camera is operating in a stand alone configuration since autoguiding controlled via CCDSoft V5 driver does not allow sub pixel guiding. With the stand alone set up, the guide scope needs to be manually aligned by adjusting 3 of the 6 collimating screw to place a suitably bright star with in the small ST-4 CCD chip. Due to the relatively large field of view of the guide scope, there are always one or more 10th magnitude stars suitable as the guide star. Once the guide star is centered, the autoguider is adjusted for a 2 seconds exposure at 2x gain and with auto dark setting placed, the calibration is started. The autoguider is active for the duration of the whole nights observation. Since the autoguider can only operate at this level of accuracy as a stand alone setup, the control cannot be done remotely which means any loss of guide star or oss of tracking can only be known when the imaging camera has completed the exposure The telescope system is housed in a home made rectangular box structure made out of styrofoam by the dow corning company. Its common use is for the insulating material for houses. However due to its strength and relatively light weight, it is a perfect product for a low cost "observatory". 10 pieces of the 200mmX60mmX30mm dimension Styrofoam was ordered. They were then glued together. As can be seen in the picture, once one side of the "box" has been removed, the whole structure can be easily toppled over to allow the telescope full access of the sky. As of now (25 February 2007) , it has operated well for about 6 months in the harsh Australian summer with no sign of wear. Inside the confinement of the observatory is also the computer system with AMD Duron processor running at 1.35Ghz. The computer is networked with the laptop inside the house where the activities were observed and if necessary controlled using UltraVNC software as the remote control software. .
|
