Celestron OMNI XLT 102 用户手册
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Special cameras have been developed for taking images of deep sky images. These have evolved over the last
several years to become much more economical and amateurs can take fantastic images. Several books have been
written on how to get the best images possible. The technology continues to evolve with better and easier to use
products on the market.
several years to become much more economical and amateurs can take fantastic images. Several books have been
written on how to get the best images possible. The technology continues to evolve with better and easier to use
products on the market.
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Your telescope makes an excellent telephoto lens for terrestrial (land) photography. Your telescope is in essence a
long focal length telephoto lens. 35mm SLR cameras are mounted directly to the telescope (using the built-in T-
Adapter on the refractors and Newtonian or using the # 93633-A T-Adapter for the Schmidt-Cassegrain). For using
a digital camera you will need the Universal Digital Camera Adapter (# 93626).
You can take images of various scenic views, wildlife, nature, and just about anything. You will have to experiment
with focusing, speeds, etc. to get the best image desired.
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The Omni Series 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 SLR cameras offer through-the-lens
metering which lets you know if your picture is under or overexposed. Adjustments for proper exposures are made
by changing the shutter speed. Consult your camera manual for specific information on metering and changing
shutter speeds.
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Releasing the shutter manually can cause vibrations, producing blurred photos. To reduce vibration when tripping
the shutter, use a cable release. A cable release keeps your hands clear of the camera and lens, thus eliminating the
possibility of introducing vibration. Mechanical shutter releases can be used, though air-type releases are best.
Blurry pictures can also result from shutter speeds that are too slow. To prevent this, use films that produce shutter
speeds greater than 1/250 of a second when hand-holding the lens. If the lens is mounted on a tripod, the exposure
length is virtually unlimited.
Another way to reduce vibration is with the Vibration Suppression Pads (#93503). These pads rest between the
ground and tripod feet. They reduce the vibration amplitude and vibration time.