Calculating Power, Maintenance, Cleaning | Meade 114ST EQ-D instruction

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from a star chart, and move the telescope in R.A. and Declination until the setting circles read the R.A. and Dec. of the object you are attempting to locate. If the above procedure has been carefully performed, the faint object will now be in the field of a low power eyepiece.

•The R.A. Setting Circle must be manually re-calibrated on the current Right Ascension of a star every time the telescope is set up, and reset to the centered object’s R.A. coordinate before moving to a new R.A. coordinate setting. The R.A. Setting Circle has two sets of numbers, the inner set is for Southern hemisphere use while the outer set of numbers (the set closest to the R.A. gear), is for use by observers located North of the Earth’s equator (e.g., in North America).

CALCULATING POWER

The power, or magnification of the telescope depends on two optical characteristics: the focal length of the main telescope and the focal length of the eyepiece used during a particular observation. For example, the focal length of the Meade 114ST EQ-D telescope is fixed at 1000mm. To calculate the power in use with a particular eyepiece, divide the focal length of the eyepiece into the focal length of the main telescope. For example, using the MA 25mm eyepiece supplied with the Meade 114ST EQ-D, the power is calculated as follows:

Power = 1000mm ÷ 25mm = 40X

The supplied 2X Barlow lens doubles the power of each eyepiece. Insert the 2X Barlow lens into the the diagonal prism, followed by the eyepiece, and secure by tightening the respective thumbscrews. For example, the 25mm (40X) eyepiece, when used with the 2X Barlow Lens, yields 80X.

The letters “MA” refers to the “Modified Achromatic” optical design, which yields corrected images. The optical design has no bearing on the power of the eyepiece.

Meade Instruments manufactures several types of eyepiece designs that are available for your telescope. The type of eyepiece (“MA” Modified Achromatic, “SP” Super Plössl, etc.) has no bearing on magnifying power but does affect such optical characteristics as field of view, flatness of field, eye relief, and color correction.

The maximum practical magnification is determined by the nature of the object being observed and, most importantly, by the prevailing atmospheric conditions. Under very steady atmospheric “seeing,” the Meade 114ST EQ-D may be used at powers up to about 228x on astronomical objects. Generally, however, lower powers of perhaps 75x to 175x will present the best images consistent with high image resolution. When unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extremely high-power eyepieces result in poor magnification, where the object detail observed is actually reduced by the excessive power.

When unsteady air conditions prevail (as witnessed by rapid “twinkling” of the stars), extremely high-power eyepieces result in poor magnification, where the object detail observed is actually reduced by the excessive power.

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 114ST EQ-D equatorial mount and tripod is factory inspected for proper fit and function prior to shipment.

The tripod legs have wingnuts (35, Fig. 1g). They may be tightened to a firm feel for a more sturdy performance of the telescope.