Most large professional telescope are constructed according to the RC principle. Until recently, these telescopes were unaffordable for amateurs. RC telescopes from Teleskop Service are primarily aimed to amateur astronomers with photographic interest. These telescopes are perfectly suited for high-resolution astrophotography. Of course, an RC can also be used for visual observing. Here, the large corrected field of view is noticeable, too. In total, the stars are sharper than, for example, in a Schmidt-Cassegrain.

The equatorial mount EQ5: The equatorial mount EQ5 carries the RC telescope with very good stability for visual observation and astrophotography. The mount comes with a sturdy stainless steel tripod, which can be extended up to 140 cm height. The mount can be upgraded from the polar finder, through motor controls to the complete GoTo control with autoguiding connection. This makes the EQ5 the ideal base for astrophotography.

The 2" Monorail Focuser: The Monorail focuser combines the ease of movement of a Crayford focuser with the stiffness of a rack-and-pinion focuser. Thus astrophotography becomes a success.

Primary and secondary mirror of quartz glass: Quartz glass does not change its dimensions if temperature changes. When the temperature changes slowly during an exposure, other mirror substrates, like Pyrex, tend to a deformation of the mirror and thus to a shift of the focus. This problem does not exist for mirrors of quartz glass. Thus the focus is better maintained which is very important for long exposures. Both mirrors are coated with 99% reflectivity. The image is obviously brighter than the one of telescopes with only 90% or 94% reflection layer.

Advantages for astrophotography: The TS Astrograph is a real Ritchey-Chrétien reflector telescope. Contrary to Maksutovs or Schmidt-Cassegrains which have spherical mirrors and need image correctors, and contrary to Newtonians that need coma correctors, the RC system is a well corrected photographical instrument that uses only mirrors (no false colour!) and does not require any corrector with many cameras.

The optical system: The RC has a concave hyperbolical primary mirror and a convex hyperbolical secondary mirror. The resulting image correction throughout the field as well as the sharpness on the optical axis are superior to typical Schmidt-Cassegrains or Newtonians. Both mirrors are ground and polished under precise computer control to diffraction-limited accuracy.

Characteristics:

• True RC Optic with a hyperbolic primary and a hyperbolic secondary mirror
• Primary and Secondary mirror are made of low thermal expansion quartz
• The Secondary mirror has a center mark for better and more simple collimation
• Large well corrected flat field without need of a separate corrector
• Enough backfocus for correctors and reducer
• Less dew problems compared to Schmidt Cassegrain or similar
• 3" Monorail Focuser with better stability
• Fast cooling down time because it is an open system
• Each RC is tested and checked on our optical bench

Delivery:

• 8" f/8 RC Astrograph
• 2" Focuser with 1:10 micro transmission
• 2 M90 tubes for reaching focus easely
• Reduction to 1¼"
• 2x Dovetails - GP level
• Skywatcher EQ5 Mount with tripod and 2 counterweights
• 8x50 finder, straight thru
• 2" diagonal with 1¼" adapter
• TS 20mm Plössl eyepiece 1¼"