Re: [ATM] Conical mirror question

["Don Clement" <clement.focuser@verizon.net>]

> The conical mirror blank is best suited for Cass type systems (in my
> opinion anyway) where the central baffle tube is also the mirror
> retainer, you still need a cell to allow you to collimate the system, so
> your not gaining all that much by going this route.

My experience with centrally supported conical mirrors is that lack of a
cell makes it easier to collimate. I have combined focusing and collimation
system around conical mirror mounted on a Bellerophon focuser. The
focuser-mirror assembly is collimated three compliant "rods" with captured
nuts by tipping and tilting the whole assembly. Focusing is by moving the
primary mirror and collimation is independent of focusing. The largest
mirror that I have mounted so far is for a 14" SCT.  I am working on larger
systems presently. For a Newt, this arraignment could make for lower inertia
telescope as it moves the focuser from being out there at the end of the
truss or tube to down below the mirror. Dave Erickson used a similar
arraignment using a Bellerophon focuser to focus the centrally mounted
conical mirror for his 8.2" F2.6 astrograph. The focuser-primary mirror
assembly is mounted on there athermal collimation rods seen on the left
(opposite the STL11K camera) in the telescope photo shown here
http://clementfocuser.com/images/Oc2226AstroTrips.pdf  The astro-photos
shown taken are good support for the conical mirrors .



Don Clement

Running Springs, California

_______________________________________________
ATM mailing list http://www.atmlist.net/