Sky & Telescope - July 2024 - 68

S&T Test Report
card has plenty of space for several
nights of shooting. The Dwarf II accepts
microSD cards with up to 512 Gb of
storage capacity.
In the Field
I used the Dwarf II for an extended
period throughout late 2023. The battery's
life depended on the temperature.
During winter at -20°C (-4°F), a full
charge lasted for about two hours of
shooting, but it lasted more than three
hours on summer nights. If power runs
low, you can plug the charger cable into
an external USB power bank without
interrupting a session.
Dew formed on the telescope on a few
summer nights, while frost was the issue
in winter. However, the glass plate over
the two lenses remained clear through
all my test nights thanks to the device's
internal heat, which helps ward off at
least mild dew and frost. At the cost of
shorter battery life, a CPU Mode option
in the Advanced Settings of the app
boosts the microprocessor's speed, which
also generates additional internal heat.
As smart as it is, the Dwarf II
cannot find the Sun or Moon on its
own and has to be manually aimed at
them using its wide-field finder view.
Once they're in the field of the main
lens, hitting Sun Track or Moon Track
(available in any of the modes other
than Astro) keeps them nicely centered
by tracking on their bright disks. And
though it does a fine job on the Sun
and Moon, it doesn't produce enough
resolution to resolve the planets as
anything more than featureless dots -
this device is mainly suited to imaging
deep-sky targets.
At night the Dwarf II finds planets
or deep-sky targets automatically by the
process of plate solving (taking a short
exposure then analyzing the image
to identify known star patterns). The
device's small size and mass allow it to
slew rapidly at 30° per second. Upon
arriving at a target, it takes an image
to determine where it's looking, then
fine-tunes its position. All this takes
only a few seconds and proved remarkably
accurate, usually placing objects
dead center on the sensor. Only targets
directly overhead presented a problem
to find and track, which is true of any
alt-azimuth-mounted scope.
Before it can perform Go To slews,
the Dwarf II must first be aligned to the
sky, a process the app calls Calibration.
This is accomplished by first rotating
the device by hand to line up two index
marks located on the back. The front of
the unit (the surface with the nameplate)
must face the direction of the
region of sky you want to explore. Then
spin the cylindrical optics tube (again,
it can be turned by hand) so the lenses
are looking at an unobstructed area
of sky. Not orienting the scope to the
proper starting position can cause it to
Top left: Objects can be selected from the Star Target screens. There is no indication which targets are above the horizon until you have tapped on
one. Top right: In Astro Mode the Feature menu contains sub-menus, some partly hidden. Clicking Settings opens the camera control menu (upper
left), where Shutter and Gain adjustments and the Infrared Cut options are found. Bottom left: Once the red shutter button is pressed, the Dwarf II
begins recording and live stacking while displaying a running count of the number of frames shot and stacked. Bottom right: This is the final livestacked
image of the Pleiades, M45, consisting of 120, 15-second subframes with just the standard in-camera stretch applied.
68 JULY 2024 * SKY & TELESCOPE

Sky & Telescope - July 2024

Table of Contents for the Digital Edition of Sky & Telescope - July 2024