ORION TELESCOPES & BINOCULARS Atlas 10 EQ 9874 Instruction Manual

19, 19 The large primary mirror and the elliptical secondary mirror of your telescope are front-surface aluminized and over-coated with hard silicon dioxide, which prevents the aluminum from oxidizing.These coatings normally last through many years of use before requiring re-coating (which is…

5, Place the O-ring that comes on the base of the bracket over the body of the finder scope until it seats into the slot on the middle of the finder scope. Slide the eyepiece end (narrow end) of the finder scope into the end of the bracket’s cylinder opposite the alignment screws whil…

14, ORION TELESCOPES & BINOCULARS Atlas 10 EQ 9874 14 collimated, the expanding disk should be a perfect circle (Figure 19). If the image is unsymmetrical, the scope is out of collimation. The dark shadow cast by the secondary mirror should appear in the very center of the out-of-focus circle, like the hole in a doughnut. If the “hole” a…

18, 18 the image appears sharp in the camera’s viewfinder. The camera’s shutter is now ready to be opened. A remote shutter release must be used or the image will be blurred beyond recognition. Try exposure times between 1 and 10 seconds, depending upon the brightness of the planet…

11, Calibrating the Right Ascension Setting Circle 1. Identify a bright star in the sky near the celestial equator (declination = 0°) and look up its coordinates in a star atlas. 2. Loosen the R.A. and Dec. lock levers on the equatorial mount, so the telescope optical tube can move freel…