6" f/12 Classical Cassegrain Telescope by GSO
Cassegrain telescopes combine the benefits of a Newtonian telescope being a pure reflective system with a short-built design. In terms of optical quality, Cassegrain telescopes are superior to customary Schmidt-Cassegrain systems. Cassegrain telescopes are mainly used for photography of the moon and the planets and for observation of astronomical objects. Thanks to the highly sensitive sensors built into modern astro cameras, even deep-sky photography of nebulae, star clusters and galaxies is possible.
The advantages of GSO Cassegrain Telescopes in summary:
Large corrected and illuminated image field due to parabolic primary and hyperbolic secondary mirror with less field curvature than with SC telescopes.
Pure reflection system without Schmidt plate, as a result even Infrared photography becomes possible at full sharpness.
Significantly quicker temperature adaption than a SC, due to open design.
Brighter image due to 96% dielectric coating on primary and secondary mirror.
No shifting, because the primary mirror is fixated
High-quality 2" Crayford focuser with micro-gear reduction and compression rings for 2" and 1.25" accessories
33% obstruction caused by secondary mirror, comparable to SC telescopes.
Better sharpness on the optical axis due to precise mirror surfaces and the lack of a Schmidt plate
Less problems from dew: with Schmidt-Cassegrains you get condensation on the front plate, not with a Cassegrain
Interior baffles for even higher contrast
Generous backfocus allowing the use of 2" accessories.
Compact tube with only 500 mm length - can be operated with smaller mounts
Significantly less expensive than other classical Cassegrain telescopes!
Cassegrain Optics are versatile Telescopes
Mobile travel scope:
Take the compact and light telescope with you to your traveling location. It only takes a few seconds to unscrew the focuser, making the Cassegrain even more compact and fitting your hand luggage.
Telescope for observation of Astronomical Objects:
Due to the bright and contrasty image and also because of the large corrected and illuminated image field, the Cassegrain is optimal for observation of astronomical objects. 2" and 1.25" accessories are not a problem. The obstruction by the secondary mirror is only 33%. This is comparable to Schmidt-Cassegrain telescopes. As a result of the 96% reflection of primary and secondary mirror the image is significantly brighter. Even the field sharpness is better, because the image field is basically undistorted.
Telescope for Astrophotography:
The Cassegrain is very well suited for photography of the moon and the planets. The visual contrast is very high. Due to interior baffles stray light is effectively suppressed. Planets and tiny moon craters can be seen without the slightest chromatic aberration. Thanks to its micro-gear reduction the Crayford focuser permits precise focusing. When using modern, highly sensitive CMOS cameras, even deep-sky photography becomes possible with the GSO Cassegrain. An additonal correction lens isn´t needed, because the image field is well corrected up to APS-C sensor format.
In The Box
6" f/12 Cassegrain
2" focuser with reduction to 1.25"
Dovetail GP Level
Dust protection cap for the focuser and front aperture
Finder shoe (mounted)
M90 extension tubes
German Collimation Manual