User`s guide

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2.2 BASIC MECHANICAL DESIGN
Figures 2-1 shows cross-sectional views of the PFE-1 when mounted to a CCD camera head.
Light enters the PFE-1 through the 1¼ inch telescope adapter and is directed either to the
focusing eyepiece or the CCD sensor by means of a flip-mirror. The focusing eyepiece
consists of a 1-inch (25.4mm) focal length Ramsden and a reticle with a precisely etched
square that defines the CCD field of view. A green LED illuminates the reticle from the
side. After a star is positioned in the reticle, the flip mirror is rotated to expose the CCD.
An exposure may now by made using the camera's control software.
Figure 2-1. Cross-sectional view of the PFE-1A mounted to a CCD camera.
The removable 1¼-inch telescope coupler attaches to any standard 1¼ inch focuser. An
optional 2-inch focusing mount adapter is available from Optec for attachment to the larger
format telescope focusers. The standard 1¼-inch coupler can be replaced with a removable
1¼-inch coupler containing a 0.5X telecompressor lens (stock no. 17610) or a 3X tele-
extender lens (stock no. 17611).