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Dec. setting‑circle
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R.A. setting‑circle
Polar axis finder (optional)
Latitude scale
Latitude adjustment
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Figure
Dec. lock lever
R.A. lock lever
R.A.
able for most telescopes. Your SkyView Pro 150mm EQ has an aperture of 150 millimeters, so the maximum magnification would be about 300x. This level of magnification assumes you have ideal conditions for viewing.
Keep in mind that as you increase magnification, the bright‑ ness of the object viewed will decrease; this is an inherent principle of the laws of physics and cannot be avoided. If mag‑ nification is doubled, an image appears four times dimmer. If magnification is tripled, image brightness is reduced by a factor of nine!
Always start with your lowest power eyepiece and work your way up. Start by centering the object being viewed in the 25mm eyepiece. Then you may want to increase the magni‑ fication to get a closer view. If the object is
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Figure 7. To find Polaris in the night sky, look north and find the Big Dipper. Extend an imaginary line from the two "Pointer Stars" in the bowl of the Big Dipper. Go about five times the distance between those stars and you'll reach Polaris, which lies within 1° of the north celestial pole (NCP).
from drifting out of your telescope’s field of view while you’re observing.
This is accomplished by slowly rotating the telescope on its right ascension axis, using only the R.A.
6.Setting Up and Using the Equatorial Mount
When you look at the night sky, you no doubt have noticed that the stars appear to move slowly from east to west over time. That apparent motion is caused by the Earth’s rotation (from west to east). An equatorial mount (Figure 6) is designed to compensate for that motion, allowing you to easily “track” the movement of astronomical objects, thereby keeping them
Polar Alignment
For Northern Hemisphere observers, approximate polar align‑ ment is achieved by pointing the mount’s right ascension axis at the North Star, or Polaris. It lies within 1° of the north celes‑ tial pole (NCP), which is an extension of the Earth’s rotational axis out into space. Stars in the Northern Hemisphere appear to revolve around the NCP.
To find Polaris in the sky, look north and locate the pattern of the Big Dipper (Figure 7). The two stars at the end of the “bowl” of the Big Dipper point right to Polaris.
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