Celestron StarSense Explorer 12" f/4.9 Dobsonian Telescope - Manual (Page 13)

ENGLISH I 13
DARK ADAPTATION AND
LIGHT POLLUTION
It takes at least a half-hour for the human eye to become dark-
adapted, so don’t immediately expect to see subtle detail in
faint deep-sky objects as soon as you get outside. While you
are observing, avoid any bright lights (like going from outside
to inside a lighted house) or else your dark adaption will need
time to reset. Use red flashlights designed for astronomical
use, as the red light will not greatly affect your night vision.
The Moon will also affect your dark adaptation, so if you
directly observe the Moon expect it to take time to regain
your night vision.
Local light pollution will greatly diminish the appearance and
contrast of fainter deep-sky objects in the telescope. Do
not expect to see much detail from urban skies. You’ll get
your best views from dark sky locations away from city or
suburban night lighting. Bright objects such as the Moon,
planets, double stars, and bright open star clusters are
not affected by light pollution as much, so they make good
objects for backyard viewing regardless of where you are.
Also keep in mind that the Moon itself can light up much
of the night sky, preventing views of faint objects even from
dark sites. So schedule deep sky observing when the Moon
won’t be visible.
USE OF FILTERS
Experiment with adding optional filters to your setup to
help improve the view. Astronomical filters thread onto the
bottom of your eyepiece and usually come in both 1.25” and
2” formats. Simply remove the eyepiece from the focuser,
thread the filter onto the bottom of the eyepiece’s barrel, and
then reinsert it into the focuser.
There are many useful filters to choose from:
Moon Filter – An essential for viewing lunar details, this filter
cuts down on glare and makes bright objects dimmer.
Variable Polarizer – Like a Moon filter, a polarizer dims your
view. The key difference is that you can customize the extent
of the dimming effect by rotating the polarizer.
Color Filters – Available in a variety of colors, these can
improve contrast when observing planetary details.
Light Pollution Filters – If you are viewing deep-space
objects from urban or suburban skies, these improve contrast
by blocking the “bad” light from local light pollution and
transmitting the “good light” from deep-sky objects. You’ll
notice the greatest improvement in contrast when observing
nebulae
NOTE ABOUT
SMARTPHONE POWER
Before going out for a night of observing with your
StarSenese Explorer Dobsonian, be sure your smartphone
is well-charged. While running the StarSense Explorer app,
the smartphone’s camera is constantly looking at the sky and
its processor is continuously determining the current sky
location, so it uses significant power. If your smartphone is
fully-charged it should last several hours but if you plan to
observe all night, we recommend bringing along a charger
for your smartphone.
Celestron offers a very handy portable charger called the
PowerTank Glow 5000, which also has a built-in red LED
flashlight. The SSE Dobs have a specific mounting location for
the PowerTank Glow 5000 that utilizes the connecting bands
which come with the PowerTank (Figure 14a). Simply mount
the PowerTank onto the posts on the base of the StarSense
dock, then connect the PowerTank to your smartphone with
your charging cable while it is in the StarSense dock. This
will provide plenty of power to your smartphone for longer
observing sessions.
Figure 14a: The PowerTank Glow 5000 mounts onto the posts on the base
of the StarSense dock using the bands included with the PowerTank.