Optical Highlights: This Tpo 6" f/9 Ritchey-Chretien Astrograph has 6" (152mm) of aperture and a focal length of 1370mm. The concave hyperbolic primary and convex hyperbolic secondary are made from a highly uniform BK7 glass blank, and finished with a scratch-resistant highly reflective 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.
Multiple Knife-Edge Baffle System: The computer designed and optimized baffle system in the TPO Ritchey-Chretien works wonders at keeping stray light at bay. Inside the tube are eight light baffles, and the primary and secondary mirrors are baffled as well.
2" Dual Speed Crayford Focuser: 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.
A Fixed Primary Eliminates Image Shift: 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.
Vixen-Style Dovetail Rail & Finderscope Base Included: A full length Vixen-style dovetail rail is attached to the TPO Ritchey-Chretien optical tube assembly for quick and easy attachment to a Vixen-style mount. The rail 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.
Long Back Focus: 150mm from the focuser or 230mm from the rear thread allows you to mount lots of imaging gear!
6" f/9 Ritchey-Chretien Astrograph
|OTA Weight||12.3 lbs.|
|Tube Color or Finish||Gloss White|
|Limiting Stellar Magnitude||13.6|
|Highest Useful Magnification||300x|
|OTA Mount Type||Vixen-Style Dovetail|