Teleskop Service has optimized this 16″ RC especiall for astro photography. The OTA comes with carbon trusses having a thermal expansion of nearly 0. The OTA weight is 37 kg and it has a Losmandy style dovetail rail on both sides.
Our 16″ f/8 RC Astrograph illuminates a max. field diameter of approx. 70 mm. Without corrector, 35 mm are possible. In the latter configuration, you have a pure mirror system without any lenses. You don´t need an IR cut filter and can use the full spectrum with a suitable CCD camera.
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. The distance from the tube backplate to the focus point is 306 mm.
To reach the perfect focus position, we suggest the GSRCV1172 und GSRCV1175 extension rings. The position of the rings is between focuser and tube backside. So you always have a good position of the draw tube.
Lightweight yet strong carbon fiber truss tubes have low thermal expansion characteristics. Shifts in focus due to temperature changes are minimized because of this design. The trusses are also designed to flex equally, keeping the optics in collimation regardless of the position of the telescope.
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, directly fitting to TS 2.5″ off-axis-guider
♦ For very heavy cameras, we offer an upgrade to a heavy focuser from Starlight or to the rack and pinion focuser TSFOCR30S from TS Optics.
The hyperbolic primary and hyperbolic secondary are made from low expansion quartz, and finished with a scratch-resistant highly reflective 99% dielectric coating for great contrast. The primary mirror is fixed in place in a metal mirror cell, and the secondary resides in a metal housing that can be collimated. The secondary mirror has a center mark for easy and accurate collimation.
The RC telescope has three small cooling fans in the rear cell that help create an ambient temperature within your telescope for more stable viewing and less fluctuation in focus. The fans are powered by an external battery pack. This battery holder accepts 8 AA batteries (sold separately).
A Fixed Primary Eliminates Image Shift:
Schmidt-Cassegrain,m EHD, ACF… & Mak-Cassegrain telescopes achieve focus by moving the primary mirror back and forth inside the optical tube assembly, and this movement can cause image shift. While manufacturers have done a pretty good job of minimizing image shift on their telescopes, a moveable mirror makes it almost impossible to eliminate it completely. The Ritchey-Chrétien has a primary that is fixed in place, removing the possibility of image shift and also the job of collimating the primary.
Why the RC Telescope is better than 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 wich is integrated in the optical system. The RC is a true reflection system without lens corrector and with a really bright image.
The optical advantages of TS RC Ritchey-Chrétien Astrographs 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.
You need a strong mount to carry the weight of 37 kg + focuser + camera equipment. We suggest:
♦ Skywatcher EQ8 / Orion HDX 110 (minimum size)
♦ 10Micron GM 2000 (minimum) or GM 3000
♦ Losmandy Titan
♦ TS WS240
|Optical Design:||True RC with a hyperbolic primary and secondary mirror.|
|Aperture:||16″ / 405 mm|
|Focal Length:||3250 mm|
|Mirror material:||low thermal expansion quartz glass primary and secondary mirrors|
|Reflectivity:||99% reflectivity non-tarnishing dielectric mirror coatings|
|Back Focus:||306 mm from tube backplate|
|Tube:||Carbon Truss Tube with 2x dovetails – Losmandy level|
|Focuser:||3″ M-LRN Monorail focuser with micro transmission and 5 kg load capacity|
|Connetion at tube side:||117 mm thread|
|Connection on eyepiece side:||M68 female, 2″ and 1.25″|
|Tube Diameter:||ca. 565 mm|
|Tube Length:||ca. 1114 mm (without focuser)|
|Tube Weight:||37 kgs|
|Dimensions shipping box:||141 x 74 x 69 cm|
|Gross weight:||45 kgs|