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You can see Venus go through its lunar-like phases. Mars will reveal a host of surface detail and one, if not both, of its polar caps. You will be able to see the cloud belts of Jupiter and the great Red Spot. In addition, you will also be able to see the Moons of Jupiter as they orbit this gas giant. Saturn with its beautiful rings is easily visible at moderate power. All you need to know is where to look. Most astronomy publications tell where the planets can be found in the sky each month. Deep-sky objects are simply those objects outside the boundaries of our solar system. They include star clusters, planetary nebulae, diffuse nebulae, double stars and other galaxies outside our own Milky Way. The Celestron Sky Maps (#93722) can help you locate the brightest deep-sky objects. You can “star hop” to an object from an area with which you are familiar. 10 Photography Hints Photographing the Moon Most deep-sky objects have a large angular size. Therefore, low-to-moderate power is all you need to see them. Visually, they are too faint to reveal any color. Instead, they have a black and white appearance. And, because of their low surface brightness, they should be observed from a dark sky location. Light pollution around large urban areas washes out most nebula making them difficult, if not impossible, to observe. LPR filters enhance deep sky viewing from light polluted areas by blocking unwanted light while transmitting light from certain deep-sky objects. You can, on the other hand, observe planets and stars from light polluted areas or when the Moon is out. Your Ceiestron can be used for both terrestrial and astronomical photography. Celestron telescopes have fixed apertures and, as a result, fixed f/ratios. To properly expose your subjects photographically you need to set your shutter speed accordingly. Most 35mm cameras offer through-the-lens metering which will let you know if your picture will be under or over exposed. This is more of a consideration when doing terrestrial photography where exposure times are measured in hundredths of a second. In astrophotography, the exposures are much longer requiring that you use the “B” setting on your camera. The actual exposure time is determined by how long you keep the shutter open. To reduce vibration when tripping the shutter, use a cable release. Releasing the shutter manually can cause vibration, something that can produce unsharp photos. A cable release will keep your hands clear of the camera and telescope, thus eliminating the possibility of introducing vibration. Mechanical shutter releases can be used, though air type releases are best. In addition, remember the focusing hints described earlier in this manual. After looking at the night sky for a while you may want to try photographing it. If you do, start with a nice, bright object like the Moon. Load your camera with film that has a moderate-to-fast speed (i.e., ISO rating). Faster films are more desirable when the Moon is a crescent. When the Moon is full, and at its brightest, slower films are more desirable. If photographing during the full phase, use a yellow filter to reduce the light intensity and to increase contrast. To attach your camera to the F80 AZ or C102-AZ, you will need the Celestron T-Adapter (#93634-A) and the T-Ring for your specific camera. On the F70 AZ, the T-Adapter is built in and you only need the T-Ring to attach your camera. Consult the Celestron accessory catalog for a list of recommended exposure times. These exposure times should be used as a starting point. Always make exposures that are longer and shorter than the recommended time. Also, try bracketing your exposures. Take a few photos at each shutter speed. This will ensure that you will get a good photo. Keep accurate records of your exposures. This information is useful if you want to repeat your results or submit them for possible publication in astronomical magazines! 11 TELESCOPE MAINTENANCE Care and Cleaning of the Optics Storing Your Telescope Refractors are generally very low maintenance telescopes. Cleaning is really all that is needed, and even that is minimal if the telescope is stored properly. Occasionally, dust and/or moisture may build up on the objective lens of your telescope. Special care should be taken when cleaning any instrument so as not to damage the optics. If dust has built up on the objective lens, remove dust with a camel’s hair brush or a can of pressurized air. Spray at an angle to the lens for approximately 2 to 4 seconds. Then, use optical cleaning solution and white tissue paper to remove any remaining debris. Strokes should go from the center of the objective lens to the outer portion. Do NOT rub in circles! With refractive lenses, never apply the cleaning solution directly to the lens. Because the elements are air-spaced, excess solution may seep between the lenses. Apply the solution to the tissue, then the tissue to the lens. You can use commercially made lens...

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