Attaching And Using The Viewfinder - Meade ETX-90AT Astro Instruction Manual

Fig. 10: Loosen control latch .
Fig. 11: High latitude leg
mounting hole and
corresponding attachment
knob.
Fig. 12: Attach telescope to
tripod.
µ
Fig. 13: Level tilt-plate.
¹
Fig. 14: Handbox HBX port.
¹
Fig. 15: Insert eyepiece.
4. Place the 26mm eyepiece (12, Fig. 15) into the eyepiece holder on the
telescope and tighten the attachment thumbscrew (13, Fig. 15) to a "firm feel" only.
Make sure that the flip-mirror control (14, Fig. 15) is in the "up" position, as shown
in the above photo. See page 8, for more information. Remove the dust cover (15,
Fig. 15) from the end of the telescope tube.
5. Make sure that the computer control panel power switch (A, Fig. 2) is in the OFF
position. Remove the Autostar handbox and the coiled cord from the packing
materials. Plug one end of the cord into the HBX port (C, Fig. 2)and the other end
of the coiled cord into the coiled cord port at the bottom of Autostar handbox, as
shown above.
6. Tighten (to a "firm feel" only, do not overtighten) the vertical lock (Fig. 6) and the hor-
izontal lock (Fig. 9).
Attaching the Viewfinder
ETX-90AT: 8 x 21mm Viewfinder: Slide the eyepiece end of the viewfinder
through the front of the viewfinder bracket (16, Fig. 18).
ETX-105AT or ETX-125AT: 8 x 25mm Right-Angle Viewfinder: Slide the front
cell end of the right-angle viewfinder through the rear of the viewfinder bracket
(17, Fig. 19).
Unthread the six alignment screws slightly to fit the viewfinder through the
bracket. With the viewfinder in place, tighten the six alignment screws to a firm feel
only against the viewfinder tube.
Using The Viewfinder
As with most astronomical telescopes, the ETX model telescopes present a fairly
narrow field of view to the observer. As a result it is sometimes difficult to locate and
center objects in the telescope's field of view. The viewfinder, by contrast, is a low-
power, wide-field sighting scope with crosshairs that let you easily center objects in
the eyepiece of the main telescope's field of view. The telescope viewfinder is a great
help in locating faint astronomical objects before you begin observing through the
telescope eyepiece.
ETX-90AT 8 x 21mm Erect-Image Viewfinder:
Standard equipment with the ETX-90AT, the 8 x 21mm Erect-Image Viewfinder has
8-power magnification and an aperture of 21mm. This viewfinder presents a
correctly oriented image both up-and-down and left-to-right.
ETX-105AT or ETX-125AT 8 x 25mm Right-Angle Viewfinder:
Standard equipment with the ETX-105AT and ETX-125AT, the 8 x 25mm Right-Angle
Viewfinder has 8-power magnification and an aperture of 25mm. This viewfinder
presents a correctly oriented image up-and-down, but is reversed left-for-right.
Fig. 18: ETX-90 Viewfinder Installation.
Fig. 16: Tighten vertical
Fig. 17: Tighten horizontal
lock.
lock.
Fig. 19: ETX-105/-125 Viewfinder
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