Collimating The Optics - Celestron STARSENSE EXPLORER 114 TABLETOP DOBSONIAN Instruction Manual

Figure 14: The tripod adapters on the bottom of the SSE Tabletop Dob base
make it easy to use the optional tripod for optimal eyepiece height.

COLLIMATING THE OPTICS

Collimation is the process of aligning the telescope's
optics. Dobsonians use the Newtonian reflector optical
design, which consists of a parabolic primary mirror and a
flat secondary mirror. To ensure the best performance, you
should periodically check the alignment of the optics. To
help with this, we have included a special "collimation cap"
you can use. In addition, the primary mirror is center marked
with an adhesive ring label to aid in collimation.
To check the alignment of the mirrors, first, remove any
eyepieces. Then, place the collimation cap in the focuser
(Figure 15).
Figure 15: To check the alignment of the mirrors, use the included
collimation cap in the focuser.
Look through the small hole in the center of the collimation
cap. The view should look like Figure 16. You'll need to
adjust the mirrors' alignment if it does not.
Reflection of
your eye
Edge of
secondary
mirror
Secondary
mirror
holder
Reflection of
secondary mirror holder
Figure 16: If your telescope is properly aligned, the view through the
collimation cap should look like the drawing above.
Bottom edge
of focuser
drawtube
Reflection
of primary
mirror
Primary
mirror clip
ENGLISH I 15