800mm (32") Cassegrain and Ritchey-Chrétien System

Quelle: ASA Astrosysteme GmbHQuelle: ASA Astrosysteme GmbH
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The AZ 800 is an AltAz mounted Telescope with Nasymth-Focus, which contains all the knowledge and experiences gained from the professional telescopes installed by Philipp Keller and is now build with the most advanced CNC from ASA.

  • Optic design by Dipl.Phys. Philipp Keller
  • Can be ordered with Cassegrain- or RC optics
  • Zero expansion AstroSitall optics from LOMO
  • Optional available are field flattener and focal reducer optimized for the given telescope
  • Motorized switch between multiple Nasmyth focus stages with a mouse click
  • ASA Direct Drive Technology
  • Suitable for Remote Observing
  • Manufactured with the latest in CNC technology in conjunction with high strength carbon fibre
  • Compact size with a moderate weight of 800kg
  • Heavy, equipment can be loaded on both focal stages without changing the center of gravity

Data sheet

Compact Size. The azimuthal design allows a very compact telescope, fitting in smaller domes compared to an equatorial telescope.

User Friendly. The Nasmyth focal point can be switched between the left and the right focus side by a mouse click within a few seconds. A direct drive motor in combination with a 0.1 arc second encoder and reference switch is used to turn the tertiary mirror. You could use one focus for visual observations while leaving your CCD camera installed on the other side. If you want to take an image of that object, all it takes is a mouse click. Of course you could also use two different CCD cameras, one installed with a ASA Reducer for wide field imaging, the other one with a Barlow lens for planetary work. Since all accessories are mounted in the center of gravity, there is no change in telescope balance when something is mounted or removed on the Nasmyth Focus. Since there is also no focuser directly at the focus (focusing for both foci is done with the secondary), the weight of the CCD or accessories can be very heavy. The comfort in visual observing is stunning compared to a classical AltAz (i.e. Dobson) or an equatorial telescope because with our telescope design the focus position and thus the view point is always at the same height.

Precise. With the AZ800 we have reached a new dimension of pointing and tracking accuracy. This is done with the direct drive and an ultra-high resolution encoder with a readout of better than 1/100 arc second directly on the telescope axis. Zero backlash, zero periodic error. ASA has sold more direct drive mounts than any other telescope manufacturer. The azimuthal design is also supporting overall better accuracies compared the equatorial telescopes because hysteresis effects, caused by optic shifts can be avoided. The ASA Derotator is correcting the field rotation that is existent in AltAz Telescopes. Even with 8m focal length seeing limited exposures without any autoguiding with 5 minutes or more is not a problem.

Perfect Optics, zero expansion. When it comes to optics, we don't compromise and use zero expansion AstroSitall optics from LOMO with lambda/8 wavefront peak to valley, measured in focus, proved with an interferogram of the complete system. These optics will not only show the lambda/8 accuracy in theory and after 20 hours cool down in the optic lab like cheap optics from borosilicate (Duran, Pyrex, Supremax etc.) but also in variable temperature conditions usually found in observatories. The optics we use are Cassegrain and RC optic sets with optional correctors. Because the mirrors are aspheric. They are more expensive compared to the much cheaper Dall Kirkham system (with one spherical mirror) but they are able to cover a much larger field. Since the basic setup uses no corrector, you can combine these systems with either a field flattener for up to 100mm field diameter or a reducer.


Please browse all accessories for Cassegrain and Ritchey-Chrétien Systems on our designated accessories page. Also note all accessories products on the menu tab: Correctors  Collimators Accessories

Prices on request!