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e writes:

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.

That's good to know. The guy who loaned it to me told me that one can
scopes like this one for about $150.

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.

I was wondering how one could test for that. Thanks.

Based on my experiences examining the scope, I had to ask myself: "What
if I loaned my scope to some bozo who decided to educate himself by taking
it apart and putting it back together. How could I develop a set of procedures
for checking everything the bozo could have messed with and, in case it
has been modified, for bringing it to a "standard" configuration. Every
scope is different, and it must depend on the scope. But I'll have that
question in mind when I look through the books you suggested.

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?

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. [snip] 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.

Thanks for the advice.
--
Ignorantly,
Allan Adler
* Disclaimer: I am a guest and *not* a member of the MIT CSAIL. My actions and
* comments do not reflect in any way on MIT. Also, I am nowhere near Boston.