User manual MEADE DS2000

[. . . ] Instruction Manual DS-2000 Series Reflecting and Refracting Telescopes Refracting Telescopes use a large objective lens as their primary light-collecting element. Meade refractors, in all models and apertures, include achromatic (2-element) objective lenses in order to reduce or virtually eliminate the false color (chromatic aberration) that results in the telescopic image when light passes through a lens. Reflecting Telescopes use a concave primary mirror to collect light and form an image. In the Newtonian type of reflector, light is reflected by a small, flat secondary mirror to the side of the main tube for observation of the image. Eyepiece F 2-Element Objective Lens Refracting Telescope In the refracting telescope, light is collected by a 2-element objective lens and brought to a focus at F. Secondary Mirror Concave Mirror F Reflecting Telescope Eyepiece In contrast, the reflecting telescope uses a concave mirror for this purpose. CONTENTS WARNING! Never use a Meade® DSTM Telescope to look at the Sun! [. . . ] Some options are choices that select the next menu level down. The Scroll keys move up and down within the list of available options, showing one option at a time. When the desired option is displayed on the second line, press the ENTER key to choose that option and move down one menu level. Fig. 20: Menus set in a loop. ENTER Select Item Object Select Item Solar System Press the MODE key to leave a level (e. g. , the wrong menu option is chosen). IMPORTANT NOTE: No matter how many levels into Autostar are traveled, each press of the MODE key moves up a level, until the top level, "Select Item, " is reached. Once in the Select Item level, press MODE to return to the topmost level, "Select Item: Object. " Fig. 21: Autostar levels. Autostar Navigation Exercise To demonstrate how the Autostar menu structure works, the following exercise calculates Sunset time so an evening observing session can be planned. NOTE: To perform an accurate calculation, Autostar must be properly initialized with the current date, time, and location of the observing site. To enter the current date, time, and location information of your observing site, see INITIALIZING AUTOSTAR, page 17, before proceeding with this exercise. 21 To Calculate Sunset time: 1. Press the MODE key several times, until "Select Item: Object" is displayed. Press the Scroll Down key once to display the "Event" option in the "Select Item" menu. Press the ENTER key to choose the "Event" option and move down a level. "Event: Sunrise" is displayed. Press the Scroll Down key once to display the "Sunset" option in the Event menu. Press the ENTER key to choose the "Sunset" option and move down another level. Autostar calculates the Sunset time based on the current date, time, and location. Autostar then displays the results of the calculation. Press MODE once to start moving back up through the Autostar levels. Press MODE again to move up another level. This is the top level, "Select Item. " Press MODE again to return to the starting point of "Select Item: Object. " Entering Numbers and Text into Autostar To enter numbers and text: I Use the Up and Down Arrow keys to scroll through numbers 0 - 9 and the alphabet. The Down Arrow key begins with the letter "A;" the Up Arrow key begins with digit "9. " Use the Right or Left Arrow key (5, Fig. 2) to move the cursor from one number to the next in the display Press ENTER when the desired information has been entered. To move the cursor across the display: I I Navigating Autostar TIP: When multiple choices are available within a menu option, the option that is currently selected is usually displayed first and highlighted by a right pointing arrow (>). [. . . ] Most impressive of these is the Great Nebula in Orion (M42), a diffuse nebula that appears as a faint wispy gray cloud. Open Clusters are loose groupings of young stars, all recently formed from the same diffuse nebula. The Pleiades is an open cluster 410 light years away (Fig. Constellations are large, imaginary patterns of stars believed by ancient civilizations to be the celestial equivalent of objects, animals, people, or gods. [. . . ]