Note: If you wish to per- form a more precise polar alignment for the purposes of astrophotog- raphy, see "Appendix B," page 50.
| Point optical |
North | tube to North |
Point counterweight shaft straight down over mount.
Level
Mount
Point leg marked with a star to North
Fig. 16a: The polar home position,
side view.
Fig. 16b: The polar home position, front view.
Speeds 1, 2, or 3: Best used for fine centering of an object in the field of view of a higher power eyepiece, such as a 12mm or a 9mm eyepiece.
Speeds 4, 5, or 6: Enables centering an object in the field of a
Speeds 7 or 8: Best used for rough centering of an object in the viewfinder.
Speed 9: Moves the telescope quickly from one point in the sky to another.
Observe the Moon
Point your telescope at the Moon (note that the Moon is not visible every night). Use your EC handbox or Autostar to practice using the Arrow keys and the slew speeds to view different features. The Moon contains many interesting features, including craters, mountain ranges, and fault lines. The best time to view the Moon is during its crescent or half phase. Sunlight strikes the Moon at an angle during these periods and adds a depth to the view. No shadows are seen during a full Moon, making the over- ly bright surface to appear flat and rather uninteresting. Consider the use of a neutral density Moon filter when observing the Moon. See OPTIONAL ACCESSORIES, page
38.Not only does it cut down the Moon's bright glare, but it also enhances contrast, providing a more dramatic image.
Tracking Objects
As the Earth rotates beneath the night sky, the stars appear to move from East to West. The speed at which the stars move is called the sidereal rate. You can setup your telescope to move at the sidereal rate so that it automatically tracks the stars and other objects in the night sky. The tracking function automatically keeps an object more or less centered in the telescope’s eyepiece.
To automatically track objects, you first need to learn how to set the polar home position of your telescope and then how to select "Targets: Astronomical" from the Autostar Setup menu. EC handbox users, see APPENDIX D, page 55, for more information.
Setting the Polar Home Position
1.Level the mount, if necessary, by adjusting the length of the three tripod legs.
2.Unlock the R.A. Lock (33, Fig. 1d). Rotate the Optical Tube Assembly until the counterweight shaft is pointing straight down over the mount. See Figs. 16a and
16b.
3.If you have not already done so, lift the telescope assembly and turn it so that the tripod leg marked with a star faces approximately North (South in the Southern Hemisphere). Release the Dec. lock (17, Fig. 1d) of the tripod, so that the opti- cal tube (10, Fig. 1a) may be rotated. Rotate the optical tube until it points North (or South in the Southern Hemisphere). Then
4.If you have not already done so, determine the latitude of your observing location. See APPENDIX C: LATITUDE CHART, page 54, for a list of latitudes of major cities around the world. Use the latitude
5.If steps 1 through 4 above were performed with reasonable accuracy, your tele- scope is now sufficiently
Once the mount has been placed in the polar home position as described above, the latitude angle need not be adjusted again, unless you move to a different geographi- cal location (i.e., a different latitude).
Important Note: For almost all astronomical observing requirements, approximate settings of the telescope’s latitude and other settings are acceptable. Do not allow undue attention to precise settings of polar home position of the telescope to interfere with your basic enjoyment of the instrument.
17
