User manual ORION TELESCOPES & BINOCULARS APEXMAKCASS

[. . . ] INSTRUCTION MANUAL Orion ® ApexTM Maksutov-Cassegrain Optical Tube AssembliesTM #9820 Apex 90mm #9823 Apex 102mm #9825 Apex 127mm Customer Support (800) 676-1343 E-mail: support@telescope. com Corporate Offices (831) 763-7000 Providing Exceptional Consumer Optical Products Since 1975 P. O. A 0000 Eyepiece adapter 25mm Sirius Plossl eyepiece Finder scope bracket Correct-image finder scope Dovetail holder 45° correct-image diagonal Focus knob Mounting block Meniscus lens Figure 1: The Apex Maksutov-Cassegrain optical tube assembly parts diagram. The Apex 102mm is shown, but all models have similar components. Welcome to a new world of adventure!Your Apex Maksutov-Cassegrain (Mak-Cass) telescope is a fine-quality instrument designed for both daytime terrestrial viewing and nighttime stargazing. [. . . ] Finder scopes can come out of alignment during transport of the telescope, so check its alignment before each observing session. If, when looking through the finder scope, you notice that the image is fuzzy, you will need to focus the finder scope for your eyes. For the 8x20 finder scope of the Apex 90mm and 102mm, this is done by rotating the finder's eyepiece. For the 6x26 finder of the Apex 127mm, this is done by first loosening the lock ring that is located behind the finder's objective lens cell (see Figure 5). Once the lock ring is loosened, thread the objective lens cell in or out until the image appears sharp. The finder scope is now focused, and should not need focusing again for your eyes. Calculating Magnification (Power) To calculate the magnification, or power, of a telescope with an eyepiece, simply divide the focal length of the telescope by the focal length of the eyepiece: Magnification = telescope focal length ÷ eyepiece focal length For example, the Apex 102mm, which has a focal length of 1300mm, used in combination with the supplied 25mm eyepiece, yields a power of: 1300 ÷ 25 = 52x. It is desirable to have a range of eyepieces of different focal lengths to allow viewing over a range of magnifications. Orion offers many different eyepieces of varying focal lengths, so check the catalog or website for a wide selection of additional eyepieces to choose from. Every telescope has a useful limit of power of about 2x per millimeter of aperture (i. e. Claims of higher power by some telescope manufacturers are a misleading advertising gimmick and should be dismissed. Keep in mind that at higher powers, an image will always be dimmer 4 Objective lens Alignment thumb screws to see what you're doing at the telescope, or to read star charts. Red light will not spoil your dark-adapted night vision as readily as white light will. To find celestial objects with your telescope, you first need to become reasonably familiar with the night sky. Unless you know how to recognize the constellation Orion, for instance, you won't have much luck locating the Orion Nebula. A simple planisphere, or star wheel, can be a valuable tool for learning the constellations and seeing which ones are visible in the sky on a given night. A good star chart or atlas, like the Orion DeepMap 600, can come in handy for helping locate interesting objects among the dizzying multitude of stars overhead. Except for the Moon and the brighter planets, it is pretty timeconsuming and frustrating to hunt for objects randomly, without knowing where to look. It is best to have specific targets in mind before you begin looking through the eyepiece. Focus lock ring Spring-loaded tensioner Eyepiece Figure 5. The steadiness of the air (the "seeing") can also limit how much magnification an image can tolerate. Always start viewing with your lowest-power (longest focal length) eyepiece in the telescope. Try using a Moon filter to dim the Moon when it is too bright; it simply threads onto the bottom of the eyepiece. B. The Planets The planets don't stay put like stars do (planets don't have fixed R. A. [. . . ] Never use regular glass cleaner or cleaning fluid designed for eyeglasses. Before cleaning with fluid and tissue, however, blow any loose particles off the lens with a blower bulb or compressed air. Stars Stars will appear like twinkling points of light in the telescope. Even the largest telescopes cannot magnify stars to appear as anything more than points of light. [. . . ]