Kaiser Wiki

Either an 8“ SCT reflector or a 5.5” APO refractor are installed in the East dome.

A somewhat older Meade LX-200 8“ refractor is mounted in the East-dome, and operated with private auxiliaries. This instrument is maintained and operated bij the “Werk Groep Oude Leidse Sterrewacht” (WLS).
The telescope was originally used for students practica on top of the Huygens building. The practica now run in the West-dome with a much more powerful Takahashi telescope.
8” Schmidt Cassegrain Telescope (1998). Focal lenght= 2000 mm. Aperture= 203 mm. Focal ratio: f/10. (14,1% obstruction). FOV: with a standard 25 mm oculair = ½⁰. Finder scope 6×50 mm, FOV: 4,5⁰.

The wedge mount from Meade was connected to the available pier. A metal groundplate supports the rather stiff mount. The handset computer supports GOTO functionality. A PC connection and software are installed to allow (remote) computercontrol.

Modern TEC 140 Apochromatic refractor. Clear aperture 5.5” / 140 mm, Focal length 980 mm, Focal ratio 7.0.
The telescope, auxiliaries, and its heavy duty portable mount, were inherited from WLS member Arie Hamer after his early death.
This telescope is currently being tested and further documented. Manual summary

Losmandy G-11 mount, fully computercontrolled.

Filterwheels, adapters, Star analyser grating (100 l/mm), solar objective filter, Bahtinov mask, CCD camera DMK 21AU618-IS 480×640 pix. Canon DSLR 450D 12Mpix with 4272 x 2848 pix. FOV LX200 31’X 21’.

The East-dome was installed about 1924, specifically for photographic photometry by Ejnar Herzsprung with a special double refractor called the “arceerkijker”. During the exposure the photographic plate was moved with very small steps to form a tiny checkerboard pattern. In this way each stellar image became a square, the density of which was a good measure for it's magnitude. De double refractor took two colors at the same time. The limiting magnitude was low: about m=7. With the introduction of the photomultiplier this approach became obsolete.