Sky and Telescope - May 2017 - 62

S&T Test Report

should consider adding a counterweight
to the rear of the tube, or purchase
the optional equatorial wedge, which
changes this "zone of avoidance" to the
area surrounding the celestial pole.
Ready to go, I prepared myself for an
adventure in wireless Wi-Fi telescope
control. I installed Celestron's free SkyPortal app, which is based on the popular SkySafari app, for my iPhone as well
as my Android tablet. While SkyPortal

only includes a couple of hundred deep
sky objects, the Plus and Pro versions of
SkySafari are compatible with the Evolution and include tens of thousands of
objects in their databases.
I initially tested the Evolution with
my iPhone, though results were identical with my Android tablet. The process
of getting aligned and going to targets is
amazingly simple. Turn on the telescope
and connect to it in the Wi-Fi setup

p Like most Celestron NexStar telescopes, the 9.25 is attached to the fork arm via a convenient
Vixen-style dovetail system that allows users to remove or re-balance the OTA, though attaching
the tube can be challenging due to the dovetail's position on the side of the tube.

M A Y 2 0 1 7 * SK Y & TELESCOPE

of the smart device (it will show up as
"SkyLink-E5" in the list of available networks). A pulsing Wi-Fi LED indicator
shows the scope is communicating with
your smart device.
Once in SkyPortal, click on the telescope icon. To perform a Go To alignment, select "connect and align" on
the screen and follow the instructions,
which will lead you through Celestron's
SkyAlign procedure. The Evo gets the
time, date, and location automatically
from your phone or tablet.
SkyAlign requires you to center three
bright objects, either stars or planets.
You don't have to know the names of
these objects; you only need to center
them. I thought I'd have a hard time
using my iPhone's touch-screen instead
of real buttons on a hand control, but
it was doable from the beginning and
became easy with experience.
The app's virtual buttons are very
responsive; there is no time-lag between
pushing one and the telescope beginning to move. I did ﬁnd the initial
rough-centering speed to be a little too
fast, but a speed-slider onscreen allows
you to adjust that and the eyepiececentering speed to suit your comfort.
I lined up the ﬁrst star in the red-dot
ﬁnder, pressed the onscreen "Enter"
button, and then positioned the star
in the eyepiece and pressed "Align." I
followed that with another star, then
Saturn, and I was done.
The app said my alignment was successful, and indeed it was. Any object
I requested the telescope to point to,
from one side of the sky to the other,
was in the 40-mm eyepiece at 59×, and
sometimes even in the 13-mm at 180×.
The Evolution can also be aligned
with the hand control, which includes
several alignment options not available
in SkyPortal. Performing the alignment
with my phone or tablet seemed to
produce the most accurate pointing. The
scope can be operated with either Wi-Fi
or with the hand control, though both
cannot be used at the same time.
So how do you point to objects with
SkyPortal? You can select a target by
clicking on it in the displayed star chart
and then clicking the Go To button, or

Sky and Telescope - May 2017

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