Thursday, April 10, 2014

New Ritchey Chrétien scope

Just a quick update to keep things flowing....
I have recently upgraded my kit to a 6in Ritchey Chrétien by Revelation Astro (from Telescope House).

Complimenting this I have a 1.25in quartz diagonal and the Celestron 8-24mm zoom eyepiece. (This beauty was first introduced to me by Al during the Sheffield Astro Star Party a few weeks ago and is a great eyepiece with a wide FOV through all the focal lengths).

Contrary to popular belief I bought the scope primarily for visual but the scope design is also superb for astrophotography as well. As both mirrors are fixed (with no corrector plate in the front) it acts like a Newtonian reflector but with the added benefit (in my opinion) of operating like an SCT. Two crucial differences are that (1) both mirrors are Hyperbolic - they bring all the wavelengths of light to the correct focal point and (2) It is coma free.
There is also a quicker cool-down time as the tube is open. There are also baffles down the length of the tube to avoid stray light, which in turn enhances contrast.

The pictures here show it mounted on the Celestron OMNI CG-4 with dual-axis drive.

First impressions are that it is a really (and I mean really!) great instrument giving pin-sharp, crystal clear images.

One of my first nights out (as I was itching to use it) was very, very poor seeing but Jupiter just sprung out. Now if a scope can do that on such a rubbish night then it surely can produce the goods when the sky is much better....

Here is a picture of Jupiter taken A-focally at about 12mm, giving 114x (I have only cropped the image to put here). The eyepiece has the great feature of having a screw adapter under the eye cup so that you can attach a DSLR directly. You have to be careful of the weight so as not to stress the diagonal, etc. but all was OK.

My next shot is of the Moon. This really can't be beaten and one thing to note is that the picture will not do justice to the shear amount of detail the scope gives, even at high power. WOW. I was not disappointed, I just wanted to see more and more. There was so much detail being shown that hadn't been apparent with other equipment. The optics of this instrument are truly AWESOME!



  1. finally, a positive review contrary to the popular belief. do you find the large obstruction in front somehow affecting your observation?

  2. Heh Syed, thanks for the comment. To answer your question - no, the secondary mirror obstruction does not affect any eye (rather than camera) viewing. I know it looks much larger than say a SCT or a standard reflector, but it works in the same way.
    All the best, clear skies.