On 29 Nov 2004 03:19:43 -0500, Allan Adler
wrote:

I doubt very much that there is a telescope that is so bad that I
can't learn something from it. Galileo discovered the moons of Jupiter
with a much worse scope. Tycho Brahe didn't even have a telescope. Neither
did Ptolemy, whose 2 millennium old astronomical contributions are immortal
and can still give an amateur plenty of work to do. I may wind up agreeing
with you about this scope, but not until after I have made every effort to
get something out of using it and examining it.

Allan, the lens mount you describe rules out a deparment store scope,
what you have is a much more expensive instrument. Meade has, and
does, import some rather poor scopes, but they also have their higher
lines, which are quite good.

Here's a quicky test for the mounting of the lens, pick any star, move
the focus until you get a blurry dot. If it's round, the lens is
mounted square, it it's an oval, the lens needs to be collumated, and
the axis that needs adjusting is 90 degrees to the shorter axis of the
image. They will interact, and it can be a long and frustrating
process to get the dot round. For visual observing, perfection is not
needed.


Which reminds me: is it better to get one dinky Unimat1 now and be able
to use all of its component machines, or get the admittedly much better
Sherline lathe now and have to wait perhaps several years to get the
Sherline milling machine? I'm finding it a tough call, not unlike the
issues raised above. If I could get the Unimat1 immediately for free under
these circumstances, I would take it and benefit from the experience of using
it. It's the same with the telescope.

If you can get one for free, go for it. Don't even think about it,
you can learn a lot from the Unimat. For a step up from the Unimat, I
would say the Taig, rather than the Sherline. Both have their
limitations, but neither of them has an advantage in the quality of
the work they can do. The quality of the work depends more on the
hands on the machine than on the machine itself. If you can get one
with all the attachments, much the better, the only limitation in what
you can attempt will be in the size of the work. For small work, and
learning purposes, they're excellent little machines.