Glenn Holliday wrote:
Several people responding to my original question suggested I post a
review of this scope. I guess case studies may be useful? OK, here
goes:

Oh, how reminiscent of a post I made on the 114mm reflector version of
the same trash that I posted here on 2001 Jan 14:

--- begin repost ---
Yesterday evening I went to dinner with some friends whose children were
given a telescope for Christmas by a cousin -- they, the parents, wanted
me to give it a once-over. The telescope itself is a Bushnell "Voyager"
114mm reflector, approx. f/8, on an EQ-1 type equatorial.

I didn't bother with the instruction sheet, but a glance at the tripod
and mount was evidence that my friends (both of whom are extremely
intelligent and practical people), had not understood the instructions.
We sorted that out, then I had a look at the telescope itself.

I was appalled at the build quality. The focuser, for example, is
entirely made of plastic and has a 0.965" insert into the 1.25"
drawtube. There was an enormous amount of slop and backlash, which was
impossible to eliminate. The finder is approx. 20mm (more about that
later). The supplied eyepieces are 20mm and 12mm Huyghenians and a 4mm
SR. There is also a x3 non-achromatic Barlow.

I suspected that it would not be collimated, so I peered down the
drawtube. It wasn't obviously out, so I removed the 0.965" insert,
perforated both ends of a 35mm film can to make a sighting tube, and
checked again. It was immediately obvious that the focuser wasn't
properly squared on -- but there was no facility for adjusting this. I
tweaked the collimation as best I could, took the scope into the garden
and set it up, then went indoors for dinner.

An hour or so later, I went outside again and tried to point it at
Jupiter. Objects are significantly dimmer in the finder than they are to
the naked eye -- the derisory aperture is obviously stopped down even
more -- I should have checked! There is a small hole/tube in the stalk
that holds the finder -- I found it to be more useful than the finder
itself.

Jupiter was disappointing in the 20mm, so I found M42 -- at least you
could see some structure. Next stop Saturn. Well, at least you could see
space between the rings and the planet, but the vibration was appalling
when I was focusing, even with the 20mm e/p. The 12mm showed no more
detail, but did introduce some false colour. This, I am happy to say,
did not prevent the exclamations of "Wow!" when people had their first
ever views of the ringed planet. The 4mm is essentially useless. I
didn't even bother trying the Barlow.

I did a quick star-test and was not surprised to find spherical
aberration.

No-one else fancied braving the cold, so we packed up and went indoors.

Throughout all this, I was trying to be extremely tactful -- I don't
think that there is much to be gained by telling youngsters that their
cherished Christmas present is a crock of excrement. I shall offer to
improve it and make it easier to use, but I am appalled! I have used
many telescopes in my life, including some that included misconceived
ideas of my own that have not exactly been a pleasure once put into
practice, but this telescope has to be one of the (if not *the*) most
difficult to use that I have ever come across. If I find it difficult,
how the heck are people with no experience going to manage? And these
are precisely the people at whom this telescope is targeted!

Nuff said!


Noctis Gaudia Carpe,
Stephen

--- end repost ---

Best,
Stephen

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