If you are like me, you spend a lot of time browsing the internet for telescope making ideas. The ATM community is one of incremental refinement, so there are many good ideas to pick and choose from to solve the issues you face.
Every so often, progress is punctuated by a big leap of innovation. When I came across Jon Pogson’s Merope thread and his Hexapod truss system, it struck me as one of the big leaps. Not because it used six tubes, but because of the implications for construction and collimation.
At the time I became aware of the Hexapod, I was well into the planning stages of a rebuild on a 16” f/7 Dob. The scope worked well, but there was a new driving force: Gen 3 Night Vision astronomy. In the f/7 scope, the NV eyepiece was the most profound leap in visual astronomy I had seen in 45+ years. So, I wanted to build a scope specifically for NV.
I was proceeding down the path of Reiner Vogel’s Low Rider concept as it would create more back-focus for focal reduction and also allow the telescope height to be lowered (since no one ever asked for a taller ladder).
After seeing Merope I attempted to create a fusion of the Low Rider and Hexapod concepts. It was proving to be a handful. Both upper end prototypes I built were unsatisfactory and the project languished.
It was time for a reset. It occurred to me that for NV performance, it would be easier to make a faster mirror slow (when needed) rather than make a slower mirror fast (which is what the image intensifier wants most of the time). Then it just became a question of “how fast”.
Conversations ensued with Mike Lockwood of Lockwood Custom Optics, and I made a deposit for a 16” f/2.8 primary mirror and 5” elliptical secondary mirror. Mike was a pleasure to deal with, one of the Good Guys in this little cottage hobby. I am glad to see him back from on CN. In addition to being very available for my design questions, Mike delivered my optics nearly a month ahead of schedule! When he releases me to share the test results on that glass, let’s just say that a lot of LZOS refractor owners will be envious. But that is the subject for another thread.
Which such a short focal length (44.7” actual ), the need for the Low Rider concept went by the wayside, allowing for a pure hexapod build. While my pace was slow (outside commitments), the build itself was actually straightforward. Perhaps even easier than the standard Obsession template.
Unfortunately I botched the last layer of a 5 color multi-cam pattern last fall. (Yes, I was the kid that flunked Art Class in the 3rd grade.) My paint shop is an unheated garage, and cold weather came early. Was I done until April?
My solution to move forward (it seemed like such a good idea at the time) was to select a paint I could apply by brush indoors - exterior latex. Fine for house, but for a telescope not so much. If you get nothing else out of this thread: never - not ever - paint a scope in latex.
The good news - such as it is - I am now positioned to capitalize on the spring/early summer observing window. This will provide operational experience and uncover any needed adjustments. When summer monsoon season hits the latex will be stripped and sanded off, and modifications implemented. The repaint will be done in airbrush-applied Durcoat, a very thin and tough paint used to camouflage firearms. Probably the same theme you see here (since I already named the scope), but with a deeper midnight blue as I had originally intended.
Enough of the Background material! Photos and feature details to follow ...
If I did not mention it, 16" @ f/2.8. Pointing at the zenith the overall height is 52". And ServoCAT of course