R.A. setting circle
Polar axis finder scope (optional)
Latitude scale (opposite side)
Latitude adjustment
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| Dec. |
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| control knob |
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| Dec. setting circle |
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| Dec. lock lever |
Right | Axis |
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Ascension | Front opening | |
Axis | Declination | R.A. lock lever |
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| |
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| R.A. |
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| control knob |
Figure 6. The SkyView Pro 120 equatorial mount.
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| Little Dipper |
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| (in Ursa Minor) |
Big Dipper | N.C.P. |
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| |
(in Ursa Major) |
| Polaris |
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Pointer |
| Cassiopeia |
Stars |
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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). |
|
Azimuth adjustment knobs
Figure 8. For polar alignment, position the tripod so that the "N" label at the base of the mount faces north. The azimuth fine adjustment knobs above it are used to make small adjustments to the mount’s azimuth position. Be certain to loosen the tripod attachment knob on the central support shaft before adjusting these knobs.
knob. But first the R.A. axis of the mount must be aligned with the Earth’s rotational (polar)
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.
Observers in the Southern Hemisphere aren’t so fortunate to have a bright star so near the south celestial pole (SCP). The star Sigma Octantis lies about 1° from the SCP, but it is barely visible with the naked eye (magnitude 5.5).
ment is sufficient.
1.Level the equatorial mount by adjusting the length of the three tripod legs.
2.There are two latitude adjustment
3.Loosen the Dec. lock lever and rotate the telescope’s opti- cal tube until it is parallel with the right ascension axis, as it is in Figure 6.
4.Move the tripod so the telescope tube and right ascen- sion axis point roughly at Polaris. If you cannot see Polaris
8