Orion 9968 instruction manual Astrophotography, Care and Maintenance, Terrestrial Viewing, Storing

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Terrestrial Viewing

Continue using stars as guideposts in this way until you are at the approximate position of the object you are trying to find (Figure 14). 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 eyepiece. Remember, the finder scope (and main telescope eyepiece, for that matter) gives an inverted image, so you must keep this in mind when starhopping from star to star.

Terrestrial Viewing

The SkyView Pro 150mm not only excels at astronomical observing, it’s great for terrestrial (land) viewing too. The equatorial mount, however, is not well suited for land viewing due to its motion about R.A. and Dec. axes instead of altitude (vertical) and azimuth (horizontal) axes. Because of this, we recommend removing the optical tube from the SkyView Pro mount and placing it on an appropriate heavy-duty photo-style tripod. Connect the optical tube to a photo tripod by threading the tripod’s 1/4"-20 shaft into one of the holes in the tube’s mounting plate.

The included mirror star diagonal, while preferred for astronomical observing because of its viewing angle and better resolution, is not optimal for land viewing because it inverts images from left-to-right. We recommend purchasing an optional 45° correct-image diagonal for terrestrial observing; it provides a more comfortable viewing angle for land viewing and an image that is oriented the same as the naked eye. In addition, an optional correct-image finder scope will be useful for aiming the optical tube.

For terrestrial viewing, it’s best to stick with low power eyepieces that yield a magnification under 100x. At higher powers, images rapidly lose sharpness and clarity due to “heat waves” caused by Sun-heated air.

Remember to aim well clear of the Sun, unless the front of the telescope is fitted with a professionally made solar filter and the finder scope is covered with foil or some other completely opaque material.

8. Astrophotography

With an optional camera adapter, the SkyView Pro 150mm EQ becomes a 1800mm f/12.0 telephoto lens for a single-lens reflex camera. For long-distance terrestrial or astronomical photography, you need only a T-ring for your specific camera model. The T-ring attaches to your camera and threads onto the eyepiece adapter (first remove the eyepiece and diagonal), coupling the camera body to the telescope (Figure 15). Use the camera’s viewfinder to frame the picture. Use the telescope’s focuser to focus the image.

You may want to consider using a remote shutter release instead of the shutter release on the camera. Touching the

Figure 14. 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 finder scope and telescope eyepiece (1). Now move the scope carefully in the direction of the next bright star (2), until it is centered. Repeat (3 and 4). The last hop (5) should place the desired object in the eyepiece.

camera can vibrate the system and blur the resulting photographic image.

9. Care and Maintenance

Storing

If you give your telescope reasonable care, it will last a lifetime. Store it in a clean, dry, dust-free place, safe from rapid changes in temperature and humidity. Do not store the telescope outdoors, although storage in a garage or shed is OK. Small components like eyepieces, diagonals, and other accessories can be kept in an optional eyepiece case. Keep the dust cover on the front of the telescope and cap the rear opening of the eyepiece adapter. Also keep the finder scope caps on if you leave it attached to the optical tube.

Eyepiece adapter

Figure 15. A 35mm SLR camera connects directly

to the eyepiece adapter with only the addition of a T-ring for your camera model.

T-ring

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Orion 9968 instruction manual Astrophotography, Care and Maintenance, Terrestrial Viewing, Storing