Terry, Two weeks ago, having gone through ever stronger power and
shorter working distance Optivisors, I finally decided I'd had enough
and bought a 'zoom boom' stereomicroscope. What an epiphany!
Originally, I'd planned to buy Zeiss surgical telescopes (James
Binnion has talked about these in previous posts) but wanted
flexibility of different powers and working distances more than
mobility. Also, there's a whole new class of stereomicroscopes with
really good optics at a third to half the price of the Zeiss
telescopes, that are entirely suitable for engraving, setting, and so
on (I plan to use mine for granulation, too). Steve Lindsay reviews
these on his website (http://www.airgraver.com/microscopes.htm),
which is where I came across them.
I contacted Mike Little (of www.microscopes.us, mentioned on the
same page), and asked some questions. Mike and his staff are
extremely helpful and knowledgeable*, making the whole process far
easier than I would've expected. In less than a week, I was setting
up my scope. My only regret is that I hadn't done this sooner. It's
completely changed everything for the better. Not only can I see
perfectly, but I don't have to wear glasses. And with a couple
auxiliary lenses, I have three nicely balanced working distances and
magnification ranges. I cut my workbench down 5" from nearly 44"
(Optivisor height for my Benchmate), so it's much easier on my arms
and wrists, and as I'm still looking through the eyepieces at the
correct height, my posture is balanced and there's no neck stiffness
whatsoever. It's surprisingly comfortable and affords a lot of moving
about -- I'd have thought it would be more restrictive. Now while I'm
certainly no expert on scopes, I've looked through a few, and this
one has big bright crispy clear 3D images. I'm sure for more money,
one could find a jazzier boom (this one's fine, though) and a heavier
head (mine's a composite), but these things aren't all that important
to me, as this isn't an industrial environment where things get
banged around by different people. So for me, the price was right and
I couldn't be happier. It is a real joy.
I realize this isn't exactly what you were asking and may be more
than you'd care to spend, but thought I'd offer it as an alternative.
And maybe it'll help someone like me (with aging diabetic eyes) who'd
about given up doing something truly enjoyable.
*Mike is to microscopes as Kenneth Singh is to jewelry tools, in my
opinion - both will patiently work with you until you get it right.
(the usual disclaimers as to self-interest apply)