Assessments - 4, GPA: 4
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Facilidade de uso
USING THE TELESCOPE With the telescope assembled, you are ready to begin observations. 1. First, pick out an easy-to-find object. Observing land objects during the daytime is a good way to become accustomed to the operation of the telescope. At night, try observing the Moon at first (if it is visible) or a bright star. NEVER POINT THE TELESCOPE DIRECTLY AT OR NEAR THE SUN AT ANY TIME! OBSERVING THE SUN, EVEN FOR THE SMALLEST FRACTION OF A SECOND, WILL RESULT IN INSTANT AND IRREVERSIBLE EYE DAMAGE, AS WELL AS PHYSICAL DAMAGE TO THE TELESCOPE ITSELF. 2. To center an object in the main telescope, first use the aligned viewfinder to find the object you wish to observe. If necessary, slightly loosen the vertical lock (5, Fig. 1) and the altitude rod lock knob (17, Fig. 1) to re-position the telescope so that the desired object can be centered in the viewfinder. When the object is centered in the viewfinder, it should then, also, be somewhere in the main telescope’s field of view. Next, using the 25mm eyepiece, center the object in the main telescope’s field of view, and sharply focus the image by turning the focus knob (23, Fig. 1). The wide-field H 25mm eyepiece included as standard equipment is the best eyepiece to use for the initial finding and centering of an object. The low-power H 25mm eyepiece presents a bright, wide field of view, ideal for terrestrial and general astronomical observing of star fields, clusters of stars, nebulae, and galaxies. For lunar and planetary viewing, switch to a higher power eyepiece such as the H 12.5mm — if you have good viewing conditions. If the image starts to become fuzzy – 6– as magnification is increased, back down to a lower power; The atmosphere is not steady enough to support higher powers. Note: Changing eyepieces changes power. 3. If you are observing an astronomical object (the Moon, a planet, star, etc.) you will notice that the object will begin to move slowly through the telescopic field of view. This movement is caused by the rotation of the Earth and makes an object appear to be moving in the telescope’s field of view. To keep astronomical objects centered in the field, simply move the telescope on one or both of its axes (vertical and/or horizontal) as appropriate. At higher powers, astronomical objects will seem to move through the field of view of the eyepiece more rapidly. Observing Tip: Place the object to be viewed at the edge of the field and, without touching the telescope, watch it drift through the field to the other side before repositioning the telescope so that the object to be viewed is again placed at the edge of the field, ready to be further observed. 4. Avoid touching the eyepiece while observing through the telescope. Vibrations resulting from such contact will cause the image to move. Avoid observing sites where vibrations may introduce image movement. Viewing from the upper floors of a building may also introduce image movement. 5. Allow a few minutes for your eyes to become “dark adapted” prior to attempting any serious observations. Use a red-filtered flashlight to protect your night vision when reading star maps, or inspecting components of the telescope. Tip: You can make your own red filtered flashlight by taping red cellophane over a flashlight lens. 6. Avoid setting up the telescope inside a room and observing through an opened or closed window pane. Images may appear blurred or distorted due to temperature differences between inside and outside air. Also, it is a good idea to allow your telescope to reach the ambient (surrounding) outside temperature before starting an observing session. 7. Planets and other objects viewed low on the horizon often lack sharpness — the same object, when observed higher in the sky, will appear sharper and have greater contrast. Turbulent air in the atmosphere can cause images to “shimmer” in the eyepiece. Try reducing power (change your eyepiece) until the image steadies. Keep in mind that a bright, clear, but smaller image is more interesting than a larger, dimmer, fuzzy one. 8. Astronomical software or a good star atlas will assist you in locating many interesting celestial objects. These objects include: • The Moon, covered with craters, mountain ranges, and fault lines. The Moon is best observed during its crescent or half phase when Sunlight strikes the Moon’s surface at an angle. It casts shadows and adds a sense of depth to the view. No shadows are seen during a full Moon, causing the bright Moon to appear flat and uninteresting. • Cloud belts across the surface of the planet Jupiter. • The 4 major moons of Jupiter, visible around the planet, changing position each night. • Saturn and its famous ring system. • Deep-Space: Nebulae, galaxies, multiple star systems, star clusters — hundreds of such objects are visible through your AstroFinder telescope. • Terrestrial objects: Your AstroFinder telescope may also be used for high-resolution land viewing. Important Note: Using the diagonal mirror r...