Orion XT10 CLASSIC, XT8 CLASSIC Care and Maintenance, Cleaning Lenses, Cleaning Mirrors

Figure 20. Starhopping is a good way to locate hard-to-find objects. Refer to a star chart to map a route to the object that uses bright stars as guideposts. Center the first star you’ve chosen

in the EZ Finder II and telescope eyepiece (1). Now move the scope carefully in the direction of the next bright star (2), until it is centered. Repeat (3&4). The last hop (5) should place the desired object in the eyepiece.

est deep-sky objects, first catalogued about 200 years ago by the French astronomer Charles Messier.

Determine in which constellation the object lies. Now, find the constellation in the sky. If you do not recognize the constella- tion on sight, consult a planisphere. The planisphere gives an all-sky view and shows which constellations are visible on a given night at a given time.

Now look at your star chart and find the brightest star in the constellation that is near the object that you are trying to find. Using the EZ Finder II, point the telescope at this star and center it on the red dot. Next, look again at the star chart and find another suitably bright star near the bright star currently centered in the finder. Keep in mind that the field of view of the EZ Finder II is 10°, so you should choose a star that is no more than 10° from the first star, if possible. Move the tele- scope slightly, until the telescope is centered on the new star.

Continue using stars as guideposts in this way until you are the approximate position of the object you are trying to find (Figure 20). Look in the telescope’s eyepiece, and the object should be somewhere within the field of view. If it’s not, sweep the telescope carefully around the immediate vicinity until the object is found.

If you have trouble finding the object, start the starhop again from the brightest star near the object you wish to view. This time, be sure the stars indicated on the star chart are in fact the stars you are centering in the EZ Finder II and telescope eyepiece. Remember the telescope and the EZ Finder II will

give you inverted images, keep this in mind when you are star- hopping from star to star.

Note About Astrophotography

SkyQuest Dobsonians are designed for visual, not photo- graphic use. The Dobsonian mount is not an equatorial-type mount, so it cannot be motor driven for long exposure astro- photography. SkyQuests have also been optically optimized for visual use, since photographic optimization degrades visu- al performance.

With that in mind, however, it is possible to do some simple astrophotography with a SkyQuest. With the use of afocal pho- tography techniques (where the camera is simply placed to the eyepiece to take a picture) and digital cameras, it is pos- sible to take pictures of bright objects. Certain photographic aids, such as the Orion SteadyPix, can help in taking photos by the afocal method.

6. Care and Maintenance

If you give your telescope reasonable care, it will last a lifetime. Store it in a clean, dry, dust free place, safe from rapid chang- es in temperature and humidity. Do not store the telescope outdoors, although storage in a garage or shed is OK. Small components like eyepieces and other accessories should be kept in a protective box or storage case. Keep the caps on the front of the scope and on the focuser when it is not in use. For maximum protection during storage, we recommend placing the telescope in a case to prevent any dust and moisture from accumulating on exposed surfaces.

The telescope requires very little mechanical maintenance. The optical tube is made of steel and has a smooth painted finish that is fairly scratch-resistant. If a scratch does appear on the tube, it will not harm the telescope. If you wish, you may apply some auto touch-up paint to the scratch. Smudges on the tube can be wiped off with a soft cloth and a household cleaner.

Cleaning Lenses

Any quality optical lens cleaning tissue and optical lens clean- ing fluid specifically designed for multi-coated optics can be used to clean the exposed lenses of your eyepieces. Never use regular glass cleaner or cleaning fluid designed for eyeglasses

Before cleaning with fluid and tissue, blow any loose particles off the lens with a blower bulb or compressed air. Then apply some cleaning fluid to a tissue, never directly on the optics. Wipe the lens gently in a circular motion, then remove any excess fluid with a fresh lens tissue. Oily fingerprints and smudges may be removed using this method. Use caution; rubbing too hard may scratch the lens. On larger lenses, clean only a small area at a time, using a fresh lens tissue on each area. Never reuse tissues.

Cleaning Mirrors

You should not have to clean the telescope’s mirrors very often; normally once every year or so. Covering the telescope with the dust cover when it is not in use will help prevent dust from accumulating on the mirrors. Improper cleaning can scratch mirror coatings, so the fewer times you have to clean the mir-

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