Orion 9874 instruction manual Astrophotography, Moon Photography, Planetary Photography

Figure 22a. First remove both the 1.25" and 2" adapters as shown.

Figure 22b. Thread the camera adapter into the focuser drawtube.

Figure 22c. The SkyView Pro 8 EQ with 35mm SLR camera attached.

Start by choosing bright objects to view. The brightness of an object is measured by its visual magnitude; the brighter an object, the lower its magnitude. Choose an object with a visual magnitude of 9 or lower. Many beginners start with the Messier objects, which represent some of the best and bright‑ 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‑ 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 21). 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.

9. Astrophotography

When coupled to a 35mm single-lens reflex camera, the Atlas 10 EQ becomes a telephoto lens. To attach a camera, you need only a T-ring for your specific camera model and the included camera adapter. First you must attach the includ‑

ed camera adapter to the Atlas 10 EQ’s focuser. To do this, remove the 1.25" and 2" eyepiece adapters from the focuser drawtube (Figure 22a). Then screw the camera adapter into the focuser drawtube (Figure 22b). Now attach the T-Ring to your camera and thread it onto the camera adapter (Figure 22c).

Use the camera’s viewfinder to frame the picture. Use the telescope’s focuser to focus the image. You may want to con‑ sider using a remote shutter release instead of the shutter release on the camera; touching the camera can vibrate the system and blur the resulting photographic image on the film. Use the focus lock knob on the focuser to fix the focus when the image is sharp.

Several different types of astrophotography can be success‑ fully attempted with the Atlas 10 EQ.

Moon Photography

This is perhaps the simplest form of astrophotography. Point the telescope toward the Moon, and center it within the cam‑ era’s viewfinder. Focus the image with the telescope’s focuser. Try several exposure times, all less than 1 second, depending on the phase of the moon and the ISO (film speed) of the film being used. A remote shutter release is recommended, as touching the camera’s shutter release can vibrate the camera enough to ruin the exposure.

Planetary Photography

Once basic Moon photography has been mastered, it’s time to get images of the planets. This type of astrophotography also works to get highly magnified shots of the Moon. In addition to the T-ring, you will need a Universal 1.25" Camera Adapter. The equatorial mount must be accurately polar aligned, too.

As before, connect the T-ring to your camera. Before connect‑ ing the universal camera adapter to the T-ring, an eyepiece must be inserted and locked into the body of the universal camera adapter. Start by using a medium-low power eye‑ piece (about 25mm); you can increase the magnification later with a high-power eyepiece. Then connect the entire camera adapter, with eyepiece inside, to the T-Ring. Insert the whole system into the focuser’s 1.25" adapter and secure firmly with the thumbscrew.

Aim the telescope at the planet (or Moon) you wish to shoot. The image will be highly magnified, so you may need to use

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