User`s guide

136 Starry Night User’s Guide
the patch of sky that you will be able to see
through a given astronomical instrument.
Therefore, the area shown inside the
indicator by Starry Night should
correspond very well to what you actually
see outdoors when you are observing.
In this section, you will learn how to create
an equipment list which has information
on all of your astronomical instruments. In
the next section, “Field of View Indicators
2 (Displaying Indicators)” on page 138,
you will learn how to display FOV
indicators onscreen for any of these
instruments.
Opening the Equipment List: Choose
Edit->Equipment List from the main
menu to open your equipment list.
Initially, this list will be blank.
Types of Equipment:
The pull-down menu in the
upper left corner of the
equipment list displays the
different types of
astronomical equipment.
Some of these pieces of equipment may be
unfamiliar to you.
• Eyepiece. For any given telescope, you
may have several eyepieces. When
viewing the same object through the
same telescope, the image that you see
will vary, depending on the eyepiece
properties. The most important
property of an eyepiece is its focal
length, which affects the image
magnification. Eyepieces with large
focal lengths (low magnification) are
good for viewing faint deep-space
objects. Eyepieces with small focal
lengths (high magnification) are good
for viewing details on bright objects,
such as the Moon or planets.
• Barlow. A Barlow lens is a device that
sits between your telescope’s focuser
and eyepiece. It is used to increase the
magnification of an eyepiece.
• Focal Reducer. A focal reducer is
essentially the opposite of a Barlow
lens. It reduces the focal length of your
telescope, decreasing the magnification
of an eyepiece.
• Finderscope. A finderscope is a
secondary telescope that attaches onto
your main telescope. It has a lower
magnification and a larger field of view
than the main scope, and is used to
locate objects in the sky, which you
will then view using the main scope.