Celestron 91525 Telescope User Manual


 
12 • Assembling Your CM-1100
The eyepiece, or ocular, is an optical element that magnifies the image
focused by the telescope. The ocular(s) fit into either the visual back directly,
the star diagonal, or the Erect Image Diagonal (purchased separately). To
install an ocular:
1. Loosen the set screw on the star diagonal until the tip no longer extends
into the inner diameter of the eyepiece end of the diagonal.
2. Slide the chrome portion of the eyepiece into the star diagonal.
3. Tighten the set screw on the star diagonal to hold the eyepiece in place.
To remove the eyepiece, loosen the set screw on the star diagonal and slide
the eyepiece out. You can replace it with another ocular (purchased sepa-
rately).
NOTE: NOTE:
NOTE: NOTE:
NOTE: The 2" mirror diagonal has a 1 1/4" eyepiece adapter to use 1 1/4"
eyepieces. You may remove the adapter to use 2" eyepieces.
Eyepieces are commonly referred to by focal length and barrel diameter. The
focal length of each eyepiece is printed on the eyepiece barrel. The longer the
focal length (i.e., the larger the number) the lower the eyepiece power and the
shorter the focal length (i.e., the smaller the number) the higher the magnifica-
tion. Generally, you will use low-to-moderate power when viewing. For more
information on how to determine power, see the section on “Calculating
Magnification.”
Installing the EyepieceInstalling the Eyepiece
Installing the EyepieceInstalling the Eyepiece
Installing the Eyepiece
Figure 2-10Figure 2-10
Figure 2-10Figure 2-10
Figure 2-10