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Getting started – Meade Instruments LX850 User Manual

Page 21

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21

Getting Started

Getting Started

Focusing and Aligning the Viewfinder

1 . If you have not already done so, insert the Meade

eyepiece into the diagonal mirror on the rear of
the OTA.

2 . With the telescope properly balanced in both axes

(See the section “ BALANCING THE TELESCOPE”
BEFORE performing this step), Unlock the RA
and DEC clutches

(Page 14, Fig. 10) so that the

telescope moves freely on both axes.

3. Point the telescope at some well-defined and

stationary land object at least 200 yards distant,
such as the top of a telephone pole or street sign.
Center the object in the telescope eyepiece (See
Focusing the Telescope section below). Re-tighten
the RA and DEC clutches.

4. With the object centered in the telescope eyepiece,

look through the viewfinder and loosen or tighten,
as appropriate, one or more of the viewfinder
collimation screws

(Page 7, Fig. 1, #2) until the

viewfinder crosshairs are precisely centered on
the object you previously centered in the telescope
eyepiece. Twist the rear section near the eyecup
clockwise or counter-clockwise to bring the object
into clear focus.

5. Check this alignment on a celestial object, such

as the Moon or a bright star, and make any
necessary refinements.

Focusing the Telescope

Meade Advance Coma-Free (ACF):
Note: All LX850 ACF optical tube assemblies ship
from our factory with a Travel Screw. This screw MUST
be removed before focusing the telescopes optics. For
details see pages 3 and 10, fig. 6b.

These optical tubes are equipped with an internal
Crayford-style, zero image shift primary mirror focuser
with dual speeds (7:1 ratio). The unique zero image
shift design eliminates the need for a primary mirror
lock and prevents image shift while focusing.

To focus the telescope, turn the outside coarse focus
knob in or out until the image is focused. For precise
focus use the smaller fine focus knob for final focus.

Meade APOs: The Meade APOs are equipped with a
precision, aluminum-machined dual speed (10:1 ratio)
Crayford-style focuser which eliminates image shift
during focusing.

To focus the telescope, turn the outside coarse
focus knob in or out until the image is focused. For

Fig 31: Balancing the StarLock assembly

Fig 32: Dual speed Crayford focuser

Fine Focus Knob

Coarse Focus Knob

Fig 33: APO Crayford focuser

Fine Focus Knob

Coarse Focus Knob