Terrestrial Observing, Astrophotography

Determine in which constellation the object lies. Now, find the constellation in the sky. If you do not recognize the constella- tions 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 you are trying to find. Using the finder scope, point the telescope at this star and center it on the crosshairs. Next, look again at the star chart and find another suitably bright star near the bright star cur- rently centered in the finder. Keep in mind that the field of view of the finder scope is approximately 5°, so you should choose another star that is no more that 5° from the first star, if possible. Move the telescope slightly, until the telescope is centered on the new star.

Continue using stars as guideposts in this way until you are at the approximate position of the object you are trying to find (Figure 16). 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.

Figure 16. 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.

8. Terrestrial Observing

The SkyView Pro 80mm ED optical tube can be used for long- distance viewing over land. For this we recommend using an optional 1.25" 45° correct-image diagonal instead of the pro- vided 2" 90° mirror star diagonal. The correct-image diagonal will yield non-reversed images and provides a more comfort- able viewing angle. To install the correct-image diagonal, first remove the 2" diagonal from the focuser drawtube by loosen- ing the two thumb screws on the drawtube. Now, place the "camera adapter" that came attached to the telescope (see Figure 4) into the focuser drawtube, and secure it with the two thumb screws on the drawtube. Now, place the correct- image diagonal into the camera adapter, and secure it with the thumb screw on the camera adapter. Place an eyepiece into the diagonal, secure it with the thumb screw on the diag- onal, and you’re ready for daytime viewing.

An optional altazimuth mount or a sturdy camera tripod, as opposed to the SkyView Pro equatorial mount, is recom- mended for terrestrial viewing. This is because the equatorial mount is designed for tracking the motion of stars, and is not easy to aim at terrestrial objects. Remove the telescope from the SkyView Pro’s tube rings, and you will notice the opti- cal tube has a mounting block on it. The mounting block will accept a 1/4"-20 thread used on most camera tripods.

For terrestrial viewing, it’s best to stick with low power eye- pieces that yield a magnification of 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 by an opaque material or removed altogether.

9. Astrophotography

With the included camera adapter, the SkyView Pro 80mm ED becomes a 600mm f/7.5 telephoto lens for a single-lens reflex camera. For long-distance terrestrial or astronomical photography, you need only a T-ring for your particular camera model. The T-ring attaches to your particular camera model and threads onto the camera adapter, coupling the camera body to the camera adapter. The camera adapter connects to the telescope in place of the 2" star diagonal. Remove the 2" diagonal by first loosening the two thumb screws on the focuser drawtube. Insert the camera adapter (with camera attached), and secure with the drawtube’s thumb screws.

Use the camera’s viewfinder to frame the picture. If you wish to rotate the field of view, simply loosen the two thumb screws on the focuser drawtube and rotate the camera body. Retighten the thumb screws once the desired orientation is achieved. Use the telescope’s focuser to focus the image. Tighten the focuser tension thumb screw to make sure the camera does not slip out of focus.

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