Changing The Magnification - Vixen SPHINX SXD Instruction Manual

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(4) Astronomical telescopes need eyepieces (ocular lenses) to view images. Confirm where
on the telescope you insert the eyepiece. This may differ from model to model. Insert a
long focal length eyepiece (large number in millimeters, low power) into the eyepiece holder
and secure it with the setscrew.
(5) Press the keys (the right on-screen soft keys on the STAR BOOK) to point the
telescope's front end toward the target object you choose. (Targets should be in excess of
200m/660ft away); a building, antenna, tower, electric pole, etc.)
(6) Look into the eyepiece. The image will likely be out of focus at first. Turn the focus
knob slowly clockwise or counterclockwise to find a point where the image in the field of
view of the eyepiece becomes sharpest.
How will the image appear in the eyepiece? The image orientation of the target object
differs depending on what type of telescope and visual accessories are used. The image
may be inverted or tilted but this does not mean the telescope is out of order. There is no
up or down in space so image orientation is not so important.
Hint 3 When using an eyepiece with short focal length, the image will be dim and the range
of sharp focus will be small. The image will be harder to see so begin with an eyepiece with
long focal length. Dividing the focal length of the eyepiece into the focal length of the
telescope gives the magnification.
Hint 4 Astronomical telescopes produce upside-down images. The telescope's image is
inverted when viewing straight-thru and mirror reversed during right-angled viewing (with
a star diagonal or a flip mirror). The non-erect orientation of a telescope's image may be
difficult to get used to.

3 Changing the Magnification

Loosen the eyepiece setscrew and change the eyepiece with a higher power eyepiece
(smaller number in millimeters). Make sure that you tighten the setscrew after changing
the eyepiece.
Re-focus the telescope by turning the focusing knobs slowly as the
higher the magnification, the smaller the range of focus.