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viewed from the eyepiece-end of the telescope.
Note: Do not overtighten the alignment screws. When tightening one screw it may be necessary to loosen
one of the two other screws.
2. Using the SP 26mm eyepiece, point the main telescope at some easy-to-find, well-defined land object,
such as the top of a telephone pole. Center the object precisely in the main telescope's field and engage
the R.A. Lock and Dec Lock so that the object can not move in the field.
3. While looking through the viewfinder, turn one or more of the 3 front-most viewfinder alignment screws (4,
Fig. 2), until the crosshairs of the viewfinder point at precisely the same position as the main telescope.
Re-check that the viewfinder's crosshairs and the main telescope are now pointing at precisely the same object.
The viewfinder is now aligned to the main telescope. Unless the alignment screws are disturbed, the viewfinder will
remain aligned indefinitely.
c. Using the Viewfinder
To locate any object, terrestrial or astronomical, first center the object in the crosshairs of the viewfinder; the object
will then also be centered in the field of the main telescope. Note: If you intend to use higher observing
magnifications, first locate, center, and focus the object using a low-power eyepiece (e.g., the SP 26mm eyepiece).
Objects are easier to locate and center at low powers; higher power eyepieces may then be employed simply by
changing eyepieces.
OBSERVING OBJECTS
1. Terrestrial Observing
The ETX Astro Telescope makes an excellent, high-resoluton terrestrial (land), telescope. Simply by setting the
telescope on its drive base, as shown in Fig. 1, the telescope may be used for an extremely wide range of land
observations. Keep in mind, however, that terrestrial images through the ETX Astro Telescope will be right-side-up,
but reversed left-for-right. Normally, such an image orientation is not bothersome, unless the observer is trying to
read a distant sign, for example. If the telescope is to be used for extensive terrestrial observations, the optional
#932 45° Erecting Prism, which yields a correctly oriented image, is recommended.
Viewing terrestrial objects require observers to look along the Earth's surface through heat waves. These heat
waves often cause degradation of image quality. Low power eyepieces, like the SP 26mm eyepiece provided with
the ETX Astro Telescope, magnify these heat waves less than higher powered eyepieces. Therefore, low power
eyepieces provide a steadier, higher quality image. If the land image is fuzzy or ill-defined, drop down to a lower
power, where the Earth's heat waves will not have such a deleterious effect on image quality. Observing in early
morning hours, before the Earth has built up internal heat, is generally more advantageous than during late-
afternoon hours.
a. Mounting for Terrestrial Applications
For use in terrestrial viewing situations the ETX Astro Telescope may be mounted in one of four ways:
1. Set the telescope's drive base on a table or other steady plafform, as discussed immediately above and as
shown in Fig. 1.
2. Attach the telescope to the optional Meade ETX Field Tripod as detailed in the instructions included with
the tripod and as shown in Figure 5. This tripod was exclusively designed for the ETX Astro Telescope to
provide extremely stable mounting not available with standard tripods.
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