Sky and Telescope - April 2018 - 60

S&T Test Report

views with a 21-mm Ethos, which gave
almost the same ﬁeld of view as the
Panoptic, but at an impressive 103×.

First Night Out
My ﬁrst night under the stars with any
telescope is usually reserved for just getting a feel for what it's like to set up and
use the equipment - serious observing
isn't typically on the agenda. As such I
picked a spot on the walkway outside
my garage where the sky is, unfortunately, heavily obscured by the house
and surrounding trees.
While I set up the scope by myself,
it would be far easier with two people.
The base with its optional motor drives
weighs about 66 pounds (30 kg). But it's
the optical assembly (a.k.a. "the tube")
that presents the biggest challenge.
Complete with the side cradles attached
to the primary-mirror assembly, the
tube weighs almost 100 pounds, and
it's quite awkward for one person to
lift and position on the base. But I still
found this easier to do than to assemble

the tube beginning with the primarymirror assembly (by itself a 60+ pound
unit) placed on the base. The problem
here for one person is trying to get the
secondary-mirror cage attached to the
top of the six truss poles while they are
pointing 7 feet above the ground and
ﬂailing around.
As twilight receded down the
western sky, I pointed the Stargate to
brilliant Vega high overhead. Although
I'm well over 6 feet tall, I could just
reach the eyepiece when standing on
a 9-inch-high step stool. At 196× Vega
appeared dazzlingly bright with four
razor-sharp diffraction spikes extending across my 18-arcminute-wide ﬁeld
of view. Boosting the magniﬁcation to
308× and racking the eyepiece from
one side of focus to the other revealed
diffraction patterns suggesting that the
optics in this scope were very good, but
Vega was really too bright for a good
star test, so I nudged the scope to the
northeast to look at Epsilon Lyrae, the
famous Double-Double.

p With the threat of rain in the forecast, the author spread out the parts of the Stargate on his
garage floor before beginning the assembly process.

A PR I L 2 018 * SK Y & TELESCOPE

Moving my eye from the Stargate's
9×50 ﬁnder to the 308× eyepiece
provided me with a dramatic, in-yourface example of the advantages that a
big aperture brings to many types of
observing. The tightly spaced components of this pair of double stars were
cleanly resolved with a wide gap of dark
sky between the tight pairs. And all four
stars were surrounded with neat sets
of diffraction rings. I've seen this kind
of clearly resolved separation at similar
magniﬁcations with smaller, highquality telescopes, but there were added
dimensions to the view in the Stargate.
Each of the four stars vividly displayed
its own delicate hue - something that is
far more subtle with smaller apertures.
And there was a multitude of faint
background stars that go mostly unnoticed in smaller scopes, giving a truly
three-dimensional feel to the scene. It
was now obvious that the optics were
indeed very good.
With my appetite whetted for more, I
decided to engage the motor drives and
attempt the necessary star alignment
for Go To pointing and tracking even
though I hadn't yet gone through the
manual for Sky-Watcher's SynScan drive
system. Following instructions that
scroll across the hand control, and after
a few false starts (mainly because of
accidentally pushing the wrong buttons
on the hand control), I got the drive
working, and I grabbed a star chart to
see what interesting objects were within

Sky and Telescope - April 2018

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