Sky and Telescope - November 2015 - 60

S&T Test Report
the mounts' pointing and tracking systems. It's one of
the big reasons I was impressed with the MyT.
Weighing only 34 pounds without the counterweight
shaft attached, the MyT certainly qualiﬁes as a portable
mount, but there's more to the story than just weight.
Power requirements and polar-alignment methods
need to be considered, since they set the MyT apart

Top: Mainly because of his experience with other Paramounts,
the author obtained "keeper" images on his ﬁrst clear night.
This one is a 30-minute exposure of the North America Nebula
made through a hydrogen-alpha ﬁlter. Above: It may be billed as
a portable mount, but the MyT is every bit at home in an observatory, where it can be run remotely over the internet from any
place in the world. Many of the author's tests were done with
the setup in his backyard observatory and controlled from his
house a few hundred feet away.

November 2015 sky & telescope

from many other portable mounts.
The MyT, like the other Paramounts, requires 48
volts DC and it comes with an AC adapter for those who
have conventional AC power available at their observing
sites. But there are also a variety of ways to power the
mount when AC isn't available. Software Bisque oﬀers
an optional adapter ($99) that delivers 48 volts DC using
EGO 56-volt lithium-ion batteries sold by Home Depot
(homedepot.com). These rechargeable batteries are
available with 2 and 4 amp-hour capacities and charging
options that can take as little as 30 minutes. Software
Bisque says that the larger battery will power the MyT
for more than 10 hours of typical use. There are also a
variety of commercial 12- to 48-volt DC converters that
will power the MyT from a 12-volt DC source such as a
car battery.
Unlike many portable equatorial mounts, the MyT
has no provision for a polar-alignment scope. You must
use other methods to align the mount's polar axis on the
celestial pole. Because the MyT has nicely engineered
azimuth and altitude adjustments on its polar axis housing, it's easy to use traditional methods such as drift
alignment to set up the mount.
But I particularly like a method that is unique to the
current Paramount line. With the base of the mount
carefully leveled, and the polar axis roughly positioned
using a compass and the elevation scale engraved on the
mount, you ﬁre up the electronics and slew the mount to
its "home" position. This position is carefully set during
the mount's construction and corresponds to a precisely
known position on the sky if the mount were accurately
polar aligned. Since the mount probably isn't aligned
at this point, you simply command the mount to slew
to any celestial object currently visible in the sky, and
using only the altitude and azimuth adjustments on the
polar axis housing, you move the mount until the object
is centered in the ﬁeld of view of whatever instrument
is on the mount. Done carefully, the method can result
in polar alignment that is suﬃciently accurate for most
astrophotography.
This alignment method does involve caveats. One is
that the process is easiest to do when there's a telescope
with an eyepiece on the mount - something I didn't
have with my imaging setup. Because my guidescope
was carefully aligned with the main telescope, my solution was to temporarily replace the small CCD guiding
camera with an eyepiece. The guidescope's 50-mm aperture was more than enough to show bright stars even
before the Sun set.
TheSkyX software supplied with the MyT includes
sophisticated methods for achieving precision polar
alignment. I've used them, and they work extremely
well, but they can be time consuming, especially if you
don't take into account a small amount of inertia that's
inherent in the mechanism on the mount's calibrated

http://www.homedepot.com

Sky and Telescope - November 2015

Table of Contents for the Digital Edition of Sky and Telescope - November 2015