GSO 10' F/8 Ritchey-Chretien - 203/1624mm RC

GSRC10M

GSO Guan Sheng Optical
in stock

GSO 10" f/8 Ritchey-Chrétien - 254/2000mm RC - Quarz Mirror

1.999,00 EUR
incl. 19 % Tax
excl.Shipping costs

Description

TS best price guarantee! - Seen elsewhere cheaper? We appreciate making you an offer: info@teleskop-service.de

10" f/8 RC Astrograph - 254mm Öffnung / 2000mm Brennweite
RC telescope for high-level astrophotography with 3" Monorail focusser

GSO RC 10

Ritchey-Chrétien (RC) telescopes are known for their excellent optical performance, especially for photographical applications. At the same time however RCs were always notorious for being very expensive. To change this the well-known US-based distributor "Astro-Tech" asked GSO to produce true RC telescopes. GSO is best known for their excellent Newtonian optics which they have built for many years now.

The result of this joint venture is an instrument that is superior in most aspects to a conventional Schmidt-Cassegrain, and still comes at a very affordable price. Teleskop-Service is European distributor for these instruments from GSO.

GSO RC10

The 10" f/8 RC Astrograph can illuminate a field diameter of max. ca. 60mm (including optional RC corrector). Without corrector, the usable field has ca. 30mm diameter. Here, you have a pure mirror system that can be used without UV/IR cut filter. Most of the CCD cameras are sensitive in this spectral range.

The image is absolutely free from chromatic abberations and the resulution is higher than most apochromatic refractors in this price range.

Technical details:

Optical Design:	true RC system consisting of a hyperpolic main- and secondary mirror.
Optical dimensions:	Aperture 10" (254mm), focal length: 2000mm, Photographic speed: f/8
Primary mirror:	Quarz - precision 1/12 Lambda or better. The main mirror is shifting free and fix installed. Reflectivity 99%, dielectrical coating.
Secondary mirror:	Quarz with 99% reflectivity coating. Mounted fully adjustable in a stiff cell. Central obstruction: 112 mm (44%)
Tube:	Metal design, weight 15.7 kgs, length 735mm incl. 3" focuser, tube diameter 294mm.
Focal plane:	110mm behind 2" connection - enough space for accessories
Baffling system:	Computer optimized, highest straylight supression.
Focuser:	Heavy-duty 3" monorail focuser (see description below)
Prism rail:	Losmandy-style 3" prism rail, adapts directly to Losmandy, CGE pro and other mounts.

The RC10's three-inch mono rail focuser:

GSO RC10 3

The 3" mono rail 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:

-- Travel: ca. 80mm
-- Free aperture: 68mm
-- Guidance: by massive and fixed steel rail
-- 1:10 transmission for precise focusing
-- 360° Rotation
-- Adaption to 2" and (when screwed off) female M69 thread, directly fitting to TS 2.5" off-axis-guider

Scope of delivery:

-- 10" f/8 RC Astrograph
-- 3" focuser with reducers to 2" and 1.25"
-- Losmandy-style prism rail

Astrophotographic Results:

Link to photographic results with the 10" RC von GSO (German language)

Optical Advantages of the GSO RC Astrographs

Optical Design: True Ritchey Chrétien / RC
The GSO 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 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.

It is for this reason that the Ritchey Chretien is very popular for astro imaging. The RC optical system (and a variant of the RC) is the most frequently used design for professional telescopes such as the 10 meter Keck telescope on Hawaii, or the VLT in Chile. Finally the RC is also available for amateurs without a "Nasa budget".

99% Dielectric High Reflectivity Coating
The primary mirror of the 8" RC is made of quartz which, similar to Zerodur, has practically zero thermic expansion for excellent optical properties during cool-down. Both primary and secondary feature a 99% high reflectivity coating which is well protected against scratches and against aging. Compared with similar instruments you get a much higher effective light gathering power.

Each optical set is tested by the manufacturer
For a constant quality level each optical set is tested and hand-corrected after the automatic production with state-of-the-art machinery. Then the optical set is tested with a Zygo interferometer. Here at TS we also test and collimate each instrument.

_____________________________________________________________________________________________

Mechanical Advantages of the GSO RC Astrographs

Fixed primary mirror cell and computer-optimized baffle system
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 GSO 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.

Computer-optimized baffles are placed inside the tube in order to eliminate stray light.

Collimation of the secondary mirror
The primary mirror is fixed in its precisely machined mirror cell. Collimation of the telescope is done through the secondary mirror. Collimation is rather easy and can even be done by an inexperienced amateur astronomer - we do however recommend to take your time with the collimation!

Picture below: the 10" GSO RC, used in Wolfi Ransburg's private observatory.

We recommend following products:

Accessories:

MNFOC25s 410,00 EUR* * excl.Shipping costs	MN3Motorfok 148,00 EUR* * excl.Shipping costs TS focus motor for 3" Monorail focusers TS & GSO RCs from 10"	MNFOC25r 410,00 EUR* * excl.Shipping costs
MNFOC25b 410,00 EUR* * excl.Shipping costs	M117-MNFOC25 90,00 EUR* * excl.Shipping costs

MFATRC

195,00 EUR*

* excl.Shipping costs

GSK10

9,90 EUR*

* excl.Shipping costs

GSO additional dust cover for 10" Newtonians and 10" RC

Optics Cleaning:

GSRCJ117

119,00 EUR*

* excl.Shipping costs

TS focuser collimation for 10" RCs (and bigger) by GSO and Astro

30A037

139,00 EUR*

* excl.Shipping costs

Geoptik Quilt Bag for Celestron & Meade SC Telescopes to 11" OTA

Adaptors:

GSRCV1172

49,00 EUR*

* excl.Shipping costs

GSO 25mm extension tube for RC focusers (10"+)

GSRCV1175

63,00 EUR*

* excl.Shipping costs

GSO 50mm extension tube for RC focusers (10"+)

BA2451566 135,00 EUR* * excl.Shipping costs Baader dovetail clamp - 3" Losmandy Level - steel - 215mm	FDR125 185,00 EUR* * excl.Shipping costs Farpoint 125mm adjustable guide scope rings for Losmandy rails	FDR108 165,00 EUR* * excl.Shipping costs Farpoint 108mm adjustable guide scope rings for Losmandy rails
FDR160 253,00 EUR* * excl.Shipping costs Farpoint 160mm adjustable guide scope rings for Losmandy rails	FDR90 139,00 EUR* * excl.Shipping costs Farpoint 90mm adjustable guide scope rings for Losmandy rails	FDA 44,00 EUR* * excl.Shipping costs Farpoint FDA - Losmandy dovetail accessory adapter

Finder & Accessories:

TSRDAV 66,00 EUR* * excl.Shipping costs TS Red Dot LED Finder - Metal Design - for Vixen Holder	TSSU850Gw 55,00 EUR* * excl.Shipping costs 8x50 Finder - with Bracket - white colour - straight through	TSSU850Ww 79,00 EUR* * excl.Shipping costs TS 8x50 Finder - with Bracket - white colour - 90° angled

Photo Acessories:

GSRCKorr 249,00 EUR* * excl.Shipping costs GSO 2" 0.75x reducer/corrector for RC telescopes	TSOAG27 169,00 EUR* * excl.Shipping costs TS Off Axis Guider - 27mm - 2" connection - for Astrophotography	TSRCFlat2 249,00 EUR* * excl.Shipping costs TS 2" corrector for GSO Ritchey-Chrétiens w/o focal reduction
INRED08 255,00 EUR* * excl.Shipping costs Intes Mikro Reducer 0.8x e.g. for Maksutov Cassegrains & RC	TS2-SC 24,00 EUR* * excl.Shipping costs Adapter: 2" receptacle / SC - SC accessories to 2"	BA2458415 32,00 EUR* * excl.Shipping costs Baader 1.25" clarity filter - full IR transmission
BA2458416 55,00 EUR* * excl.Shipping costs Baader 2" clarity filter - full IR transmission	CCDT67 185,00 EUR* * excl.Shipping costs Astro Physics CCDT67 0.67x Reducer 2" - e.g. for GSO RC

Alternatives to this product - Suggestions from TS:

M117-FTF2535

70,00 EUR*

* excl.Shipping costs

M117-BASTR3

70,00 EUR*

* excl.Shipping costs

upUser reports

Astrophotographic Results:

Link to photographic results with the 10" RC von GSO (German language)

__________________________________________________________________________

M1 Crab Nebula durch den 10" RC von GSO - ohne Korrektor - von Wolfi Ransburg

Ich habe den 10" RC mittlerweile als Hautpinstrument in meiner Sternwarte, weil das Teleskop selbst unter durchschnittlichen Bedingungen (Stadtrandlage in München) durch die hohe Kontrastleistung und die gute Schärfe schöne Ergebnisse bringt. M1 wurde insgesamt 195 Minuten belichtet. Um den ca. 23mm durchmessenden Chip voll auszuleuchten und auch mit hoher Feldschärfe abzubilden, war kein Korrektor nötig.

Die Aufnahme zeigt das volle unbeschnittene Feld mit der ATIK 4000
.......................................................................................... Link zu mehr Infos und einer größeren Darstellung

M76, captured with the GSO 10" Ritchey-Chrétien
a first test shot, captured under slightly adverse conditions (bad seeing, crescent moon, suburb east of Munich)

M76 with GSO RC10

Instrument: GSO 10" RC
Camera: ATIK 4000
LRGB - 30 min luminance and 30 min RGB
(c) by Wolfi Ransburg