This 8" f/8 Ritchey-Chretien Carbon Fiber Astrograph telescope has 8" (200mm) of aperture and a focal length of 1600mm. The concave hyperbolic primary and convex 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 computer designed and optimized baffle system in the TPO Ritchey-Chretien works wonders at keeping stray light at bay. Inside the tube are ten light baffles, and the primary and secondary mirrors are baffled as well. Besides being very high tech and impressive-looking, carbon fiber is light-weight, strong, and has a lower coefficient of expansion than aluminum. That means your OTA will be tough and not weigh more than it has to, but also that your focus won't tend to shift as temperatures change throughout the night.
You'll love the 2" 1:10 Dual Speed Crayford focuser that comes standard on this RC. The dual knobs allow you choose the speed with which you focus. One turn of the larger knob equals ten turns of the smaller knob, so minute adjustments…when you are "almost there"…are easy to do with this high quality focuser. A 1.25" compression ring adapter is also included so you can use both 2" & 1.25" eyepieces. Two spacers are included as well, which allows you to adjust the focus position for different cameras with various back focus requirements. Schmidt-Cassegrain & 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-Chretien has a primary that is fixed in place, removing the possibility of image shift and also the job of collimating the primary.
Talk about versatility! A Losmandy-style dovetail is attached to the bottom of the OTA, and a Vixen-style dovetail rail is attached to the top for quick and easy attachment to a variety of mounts. The rails can be removed if you wish to use mounting rings (sold separately) instead. While a finderscope is not included, the OTA comes standard with a finderscope base that will accept Vixen-style brackets (if you want an optical finder) or most red dot finders.
8" f/8 Ritchey-Chretien Astrograph
|Warranty||2 Year Warranty|
|Optical Tube Weight||16.4lbs|
|Optical Coatings||99% Dielectric|
|Tube Finish||Carbon Fiber Look|
|OTA Mount Type||Losmandy-Style Dovetail|