Celestron StarSense Explorer 150mm Smartphone App-Enabled Tabletop Dobsonian Tel - Page 13

DARK ADAPTATION AND LIGHT POLLUTION It takes at least a half-hour for the human eye to become dark-adapted, so don't immediately expect to see subtle detail in faint deep-sky objects as soon as you get outside. While you are observing, avoid any bright lights (like going from outside to inside a lighted house) or else your dark adaption will need time to reset. Use red flashlights designed for astronomical use, as the red light will not greatly affect your night vision. The Moon will also affect your dark adaptation, so if you directly observe the Moon expect it to take time to regain your night vision. Local light pollution will greatly diminish the appearance and contrast of fainter deep-sky objects in the telescope. Do not expect to see much detail from urban skies. You'll get your best views from dark sky locations away from city or suburban night lighting. Bright objects such as the Moon, planets, double stars, and bright open star clusters are not affected by light pollution as much, so they make good objects for backyard viewing regardless of where you are. Also keep in mind that the Moon itself can light up much of the night sky, preventing views of faint objects even from dark sites. So schedule deep sky observing when the Moon won't be visible. USE OF FILTERS Experiment with adding optional filters to your setup to help improve the view. Astronomical filters thread onto the bottom of your eyepiece and usually come in both 1.25" and 2" formats. Simply remove the eyepiece from the focuser, thread the filter onto the bottom of the eyepiece's barrel, and then reinsert it into the focuser. There are many useful filters to choose from: Moon Filter - An essential for viewing lunar details, this filter cuts down on glare and makes bright objects dimmer. Variable Polarizer - Like a Moon filter, a polarizer dims your view. The key difference is that you can customize the extent of the dimming effect by rotating the polarizer. Color Filters - Available in a variety of colors, these can improve contrast when observing planetary details. Light Pollution Filters - If you are viewing deep-space objects from urban or suburban skies, these improve contrast by blocking the "bad" light from local light pollution and transmitting the "good light" from deep-sky objects. You'll notice the greatest improvement in contrast when observing nebulae ENGLISH I 13