Celestron C4.5 User Manual

Collimation
46 œ Telescope Maintenance
The
optical
performance
of
your
Celestron
C4.5
telescope
is
directly
related
to
the
alignment
of
the
optical
system,
more
commonly
referred
to
as
colli-
mation.
Your
C4.5
was
collimated
after
it
was
completely
assembled.
However,
if
the
telescope
is
dropped
or
jarred
severely,
it
may
have
to
be
recollimated.
There
are
two
optical
elements
that
may
need
to
be
adjusted.
They
are
the
primary
and
secondary
mirrors.
To check the collimation of your telescope:
1. Point your telescope at a well-illuminated object like a wall or the
daylight sky (away from the Sun).
2. Remove the accessory adapter and the long black tube that threads into
the focuser.
3. Look into the opening in the focuser. You will see three things:
* The reflection of your eye in the secondary mirror.
* The reflection of the secondary mirror on the primary mirror and its
support arms.
* The reflection of the primary mirror in the secondary mirror. You will
also see part of the inside of the tube.
4. Compare the view seen through the telescope with the illustration
below. If the image seen through the telescope looks like this illustration
then your telescope is out of collimation.
There are two types of adjustments that need to be made to correct this,
which are the primary and secondary mirrors. Generally, you will adjust the
primary mirror more often than the secondary mirror. These adjustments
are described separately in the following sections.
Figure 8-1
This illustration shows the image seen through a poorly collimated C4.5
Newtonian telescope. In this case, both the primary and secondary
mirrors need adjusting.

Celestron C4.5 Specifications

General

Brand	Celestron
Model	C4.5
Category	Telescope
Language	English