Introduction
A
small, fast refractor is the ideal telescope. The short focal length makes it almost as compact as a similar
reflector while costing several times more. A rather restricted aperture enables one to practice their
averted-vision techniques while searching for deep-space objects such as M31. Planetary observation is a strength of
these instruments and the necessary magnification is easily obtained by stacking
two or three barlow lenses. Chromatic
aberration is an important criterion and these scopes have plenty of it.
Higher quality scopes use exotic and expensive lenses that can actually
reduce chromatic aberration to that of a good f/15 Tasco.
With these points in mind, I set out to find my ideal scope.
I
began my search by reviewing the latest offerings from the major manufactures.
However, I longed for something different.
Several months of searching the used telescope market turned up a lead. After careful consideration I purchased
the short-tube refractor that is the subject of this review: the Fisher Price
short tube shown in Figure 1. This
model was only produced from 1986 to 1990. To buy one, you will have to find someone willing to part with
theirs. Keep in mind that these
scopes hold their value very well in spite of often being well used.
Figure 1. My ideal telescope: the
Fisher Price Short Tube #6605. Brilliant
red with handsome appointments, this scope stands out in a crowd.
Optical
Tube
The
tube is made in the United States from a light-weight space-age material. Unlike many other so-called high-end scopes,
the manufactureÕs name is embossed and painted with gold lettering.
Inside, the tube has a finish similar to its outside.
The lens shown in Figure 2 is a high-quality air-spaced doublet. In spite of being almost a twenty-year-old
design, the lens is heavily stopped down. The tubeÕs delicate objective is protected
by an integral rubber dew shield. One
feature that isnÕt found on any other high-end refractor is an integral storage
compartment (see Figure 3) that also forms part of the dove tale.
Overall, the fit and finish of the OTA are well above average.
Figure 2. The objective is an air-spaced
doublet and the optical tube is well baffled
 
Figure 3. An integral storage compartment
holds the filters.
Focuser
The
focuser shown in Figure 4 is an excellent rack-and-pinion design with a generous
40 mm of travel. Control is very
precise: thereÕs no glue grease on this puppy. The large knobs make focus adjustment easy even for those with
very small hands.
Figure 4. The rack-and-pinion focuser
is silky-smooth and has tonnes of travel.
Mount
A
nifty matching table-top tripod is included (an option on even the most expensive
modern refractors). Although
very light, the mount is solid - in contrast to modern extruded aluminum mounts.
Illustrated in Figure 5 is the very cool way the tripod folds for storage. Tension in altitude is adjustable.
Figure 5. The tripod folds for
storage.
Eyepiece
This
scope was available with a range of magnifications: this example has the very-wide-field
7X eyepiece. An unusual aspect
of this scope shown in Figure 6 is that the eyepiece is integral to the star
diagonal. It is well-matched
optically to the main objective and has a rubber eyecup. Eye relief is excellent.
Figure 6. The eyepiece is integral
to the star diagonal and has a slot for the included filters .
Accessories
Included
were a number of specially-designed filters (Figure 7), which slide under
the eyepiece. With these, image
resolution and contrast improved several orders of magnitude.
Figure 7. Included was a set of
very good filters .
Performance
ItÕs
the lightest scope IÕve used and is an excellent Ōgrab-and-goĶ scope. Set up and cool down was fast...really
fast. The focuser is a joy to
use and is certainly better quality than many Chinese-made units. Optics are textbook - in more ways than
one. The low power eyepiece yielded
a very wide field-of-view. Views
of the moon were truly amazing with purple haze no worse than that produced
by other high-end short-tube refractors. Galaxies and diffuse nebula were easily viewed by using generous
quantities of averted vision. For
astrophotography the scope was mounted to a Losmandy GM8 (see Figure 8) which
is about the minimum requirement for this type of work: an EQ-5 isnÕt up to
the task. As expected, views
of planets are small, however the included filters improved contrast as illustrated
by the image of Jupiter shown in Figure 9.
Figure 8. For astrophotography
this scope is an ideal match for the Losmandy GM8.
Figure 9. This image of Jupiter
was obtained through the eyepiece [it really was!] with a Canon A70 digital
camera and a Fisher Price #4 red filter.
Conclusions
In
the end is it a good scope? For
the price you will be fishing to do better.
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