TS 10 inch f/8 Ritchey-Chrétien Astrograph on EQ6-R GoTo Mount

TS-Optics 10 inch f/8 Ritchey-Chrétien Astrograph on EQ6-R GoTo Mount

Ritchey Crétien telescope for demanding astro imaging and observing.

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 mount

Die EQ6-R Pro Synscan from Skywatcher carries the RC with good stability and allows fast slewing speeds and very precise tracking. The internal database with 42.000 objects, the ST-4 autoguider port and the accurate zero-play power transmission (belt drive)make this mount a good base for astro photography.

• precise tracking and autoguiding connection for astrophotography
• powerful and silence stepper motors for maximum speed 3.4° per second
• Accurate zero-play power transmission thanks to synchronous belt drive
• Illuminated polfinder is included

The 3" M-LRN Monorail Focuser:

The 3" Monorail focuser is a further development of the Crayford design. The load is not carried by four (often underdimensioned) ball bearings but on a stainless steel track on the base, thus preventing tilting and bending even under high loads. It is countered by a big knurled screw that centers the inner tube exactly to the rail. The load is distributed evely across the rail´s surface. Technical details of the focuser:

• Travel: ca. 80 mm
• Clear aperture: 68 mm
• Guidance: by massive and fixed steel rail
• 1:10 transmission for precise focusing
• 360° rotation
• Adaption to 2" and (when screwed off) female M68 thread
  

Features of the TS RC Telescopes

• 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
• 99% reflectivity non-tarnishing dielectric mirror coatings
• 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
• Fast cooling down time because it is an open system
• Each RC is tested and checked on our optical bench
  

Low Thermal Expansion Quartz Primary and secondary mirrors

Designed
for astro imaging, TS RC mirrors are made of low thermal expansion
quartz, rather than the ordinary optical glass used by competitors.
Ground and polished under precision computer control to
diffraction-limited accuracy. Both primary and secondary mirrors have a
full 99% reflectivity for the brightest possible images. This is
substantially higher than the 88% reflectivity of competitors’
conventional aluminum coatings or the 94-96% reflectivity of enhanced
aluminum coatings.

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.

Advantages to Schmidt Cassegrain telescopes with correctors

This
is also the advantage of RC telescopes against Celestron EHC or Meade
ACF telescopes. These telescopes needs a lens corrector which is
integrated in the optical system. The RC is a true reflection system
without lens corrector and with a really bright image.

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.

No shifting

Most
similar telescopes have a movable primary mirror cell. When focusing
the telescope the entire mirror is moved. Unfortunately this technique
invariably leads to a certain amount of image shift. Most manufacturers
have controlled this problem to a fair extent, but the remaining image
shift can be quite distracting for astro-imaging, particularly with
cameras with a small sensor size or when taking series of frames with
several hours of total exposure time. In the TS RC the mirror sits in a
fixed mirror cell and focus is changed with a separate focuser. This
eliminates the problem of image shift completely.

Delivery contents

• 10" f/8 RC Astrograph
• 3" Focuser with 1:10 micro transmission
• Reduction to 2" and to 1.25"
• 2x Dovetails - Losmandy level
• Skywatcher EQ6-R Pro Synscan Mount with tripod and 2 counterweights
• One additional 5 kg counterweight
• 8x50 finder, straight
• 2" diagonal with 1.25" adapter
• TS 32 mm Plössl eyepiece 1.25"

How to find the focus:The TS RC has a generous back focus allowing to attach many accessories like off-axis guiders, filterwheels and much more