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MAINTENANCE
Cleaning
As with any quality instrument, lens or mirror surfaces should be cleaned as infrequently as possible. Front
surface aluminized mirrors, in particular, should be cleaned only when absolutely necessary. In all cases
avoid touching any mirror surface. A little dust on the surface of a mirror or lens causes negligible loss of
performance and should not be considered reason to clean the surface. When lens or mirror cleaning does
become necessary, use a camel’s hair brush or compressed air gently to remove dust. If the telescope’s
dust cover is replaced after each observing session, cleaning of the optics will rarely be required.
Mount and Tripod Adjustments
Every Meade 114 EQ-ASB equatorial mount and tripod is factory inspected for proper fit and function prior
to shipment.
The tripod legs have wingnuts (
39, Fig. 1c), and Phillips-head screws (38, Fig. 1c) that may have backed
off. They may be tightened to a firm feel for a more sturdy performance of the telescope.
Collimation (Alignment) of the Optics
All Meade 114 EQ-ASB telescopes are optically aligned at the factory prior to shipment. It is unlikely that
you will need to align, or collimate, the optics after receipt of the instrument. However, if the telescope
received unusually rough handling in shipment, it is possible that the optics must be re aligned for best
optical performance. In any case this alignment procedure is simple, and requires only a few minutes the
very first time the telescope is used. Take the time to familiarize yourself with the following collimation
procedure, so that you will recognize a properly collimated instrument and can adjust the collimation
yourself, if necessary.
a. Correct collimation
The properly collimated (aligned) mirror system in the Meade 114 EQ-ASB assures the sharpest images
possible. This occurs when the primary mirror and diagonal mirror are tilted so that the focused image (see
Fig. 4) falls directly through the center of the focuser drawtube (17, Fig. 1b). These mirror tilt adjustments
are made with the diagonal assembly (
Fig. 5) and the primary mirror cell (Fig. 6), and will be discussed
later.
To inspect the view of the mirror collimation, look down the focuser drawtube with the eyepiece removed.
The edge of the focuser drawtube (
1, Fig. 7), will frame the reflections of the primary mirror with the 3 mirror
clips (
2, Fig. 7), the diagonal mirror (3, Fig. 7) , the spider vanes (4, Fig. 7), and your eye (5, Fig. 7).
Properly aligned, all of these reflections will appear concentric (i.e., centered) as illustrated in
Fig. 7.
Any deviation from the concentric reflections will require adjustments to the diagonal assembly (
Fig. 5),
and/or the primary mirror cell (
Fig. 6).
b. Diagonal holder adjustments
If the diagonal mirror (
1, Fig. 8) is centered in the drawtube (2, Fig. 8), but the primary mirror is only partially
visible in the reflection (
3, Fig. 8), the 3 Phillips-head diagonal tilt screws (1, Fig. 5). Note: To adjust these
screws you must first remove an adhesive backing) must be unthreaded slightly to the point of where you
can tilt the diagonal holder (
3, Fig. 5) from side-to-side by grasping the diagonal holder with your hand and
tilt until you see the primary mirror become as centered in the reflection of the diagonal mirror as possible.
Once you are at the best position, thread in the 3 Phillips-head diagonal tilt screws to lock the rotational
Monture
Diagonale
Miroir Diagonal
Image Focalisée
Miroir Primaire
Vis D'inclinaison
du Miroir Primaire
Fig. 4: The Newtonian Reflecting Telescope.
Diagonal
Assembly
Diagonal Mirror
Focused Image
Primary Mirror
Promary Mirror-Tilt
Screws
