Sky and Telescope - August 2017 - 60

S&T Test Report

p The center of the primary mirror is marked by
a white circle. But users must supply their own
collimation eyepieces or lasers.

at high power when placed on a sturdy
equatorial mount, but that loses the
beneﬁt of portability; the combination is
as heavy as a standard 8-inch Dobsonian
and considerably less capable.
When used with its tabletop mount,
the scope needs - or at least deserves
- a custom-built support to raise it to
an appropriate height. If you place it
on a conventional table, the eyepiece
is too high for use while sitting in a
conventional chair and a bit low for a
standing adult. Also, few portable tables
are sturdy enough to permit the scope
to be used at high power. Unlike many
tabletop scopes, the Z130's base is too
big to ﬁt on a chair or stool.
If you're handy with tools and have
a saw that can make accurate angled
cuts, a support with splayed legs like
the one under "DIY Improvements" at
eyesonthesky.com is ideal. Having only
hand tools, I built a small table with
vertical legs from a scrap of ¾-inch
plywood, a length of 2×2 lumber, and
six angle irons to keep the structure
rigid. It works very well indeed when
I'm sitting in a conventional chair, and
when I turn the table upside down, the
60

A U G U S T 2 0 1 7 * SK Y & TELESCOPE

scope nests inside it for storage. But the
combination of table and scope, while
much lighter than a 6-inch Dob, is right
at the limit of what I consider to be easily portable in a single trip.
Once it's set up, this telescope is
a joy to use. When I set the eyepiece
angle appropriately, I can view all the
way from the horizon to the zenith in
perfect comfort. My head is above the
eyepiece when it's at its lowest and level
with the eyepiece when it's highest, and
the two effects cancel out almost perfectly. My only complaint is that it's a
little hard to rotate the tube in azimuth
when it's pointing near the zenith. This
is an issue with all Dobs, but the short
tube exacerbates the problem. I found
that the best solution was to get more
leverage by grabbing hold of the turntable base rather than the tube.
Star-testing indicates that my Z130's
mirror has a slight turned-down edge.
That's probably responsible for the fact
that Jupiter appears somewhat soft.
Although the Z130 provides good views

of the Great Red Spot at 130× during
moments of excellent seeing, these
moments are rarer and less sharp than
in my premium-quality 7-inch Dob
when I set the two up side by side. Still,
the scope shows Cassini's Division in
Saturn's rings with ease, and at 162× on
one night of unusually steady seeing, I
got a good view of Mare Erythraeum on
Mars when the planet was just 11 arcseconds across. That's impressive for a
mass-produced mirror of this aperture!
As for deep-sky observing, the scope
shows all the Messier objects with ease
under dark skies, and it has enough
aperture to resolve dozens of stars in
the brightest globular clusters. The
improvement over a 114-mm scope is
bigger than you might guess from the
numbers alone. The Zhumell 130 is an
outstanding performer for its amazingly
low price.
¢ S&T Contributing Editor TONY
FLANDERS is a long-time fan of simple,
inexpensive telescopes.

p The author built a low table to support the telescope out of scraps of wood. When the table is
turned upside down, the telescope nests inside it during transport.

http://www.eyesonthesky.com

Sky and Telescope - August 2017

Table of Contents for the Digital Edition of Sky and Telescope - August 2017