Metering

The NexStar has a fixed aperture 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.

Reducing Vibration

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. These pads rest between the ground and tripod feet. They reduce the vibration amplitude and vibration time.

CCD Imaging

Fastar Lens Assembly Option – Using your NEXSTAR GPS telescope at f/2 with optional Fastar Lens Assembly

The NexStar GPS telescope is equipped with a removable secondary mirror that allows you to convert your f/10 telescope into an f/2 imaging system capable of exposure times 25 times shorter than those needed with a f/10 system! With the optional Fastar lens assembly you can easily convert your Fastar compatible telescope to f/2 prime focus use in a matter of seconds. The NexStar's versatility allows it to be used in many different f-number configurations for CCD imaging. It can be used at f/2 (with optional Fastar Lens Assembly), f/6.3 (with the optional Reducer/Corrector), f/10, and f/20 (with the optional 2x Barlow) making it the most versatile imaging system available today. This makes the system ideal for imaging deep-sky objects as well as planetary detail. Described below is the configuration of each F-number and the type of object best suited to that kind of imaging.

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Celestron 93507 manual CCD Imaging, Metering, Reducing Vibration
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93507 specifications

The Celestron 93507 is a powerful and versatile telescope designed for both amateur and seasoned astronomers. This model combines advanced technologies and practical features to deliver an enriching stargazing experience. One of the standout characteristics of the Celestron 93507 is its robust optical design. It features a 90mm aperture, allowing users to capture bright, detailed views of celestial objects, from the lunar surface to distant galaxies. The telescope employs a Maksutov-Cassegrain optical design, known for its compact form factor and high-quality images, free from chromatic aberration.

In terms of usability, the Celestron 93507 is designed with an easy setup in mind. It comes equipped with a solid mount that provides stability during observation. The mount also includes slow-motion controls, facilitating smooth panning across the night sky, allowing astronomers to track celestial objects effortlessly. This feature is particularly beneficial for viewing planets and other fast-moving astronomical phenomena.

Furthermore, the telescope comes with high-grade optics, including fully coated glass elements that enhance light transmission and ensure sharper images with higher contrast. It includes two eyepieces — a low-power 25mm and a high-power 10mm — that provide versatility in viewing options, whether you’re looking at wide expanses of the night sky or zooming in on close details of lunar craters.

Additionally, the Celestron 93507 is compatible with various Celestron accessories, including solar filters and advanced eyepieces, enabling users to expand their observational capabilities. The telescope's compact design makes it portable, perfect for amateur astronomers who enjoy taking their telescope for trips to dark-sky locations.

Another noteworthy feature of this telescope is its durability. Built to withstand the rigors of outdoor usage, the materials used in the Celestron 93507 are resistant to wear and tear, ensuring that users can enjoy stargazing for years.

Overall, the Celestron 93507 is a well-rounded instrument that combines advanced optical technology, user-friendly features, and portability, making it an excellent choice for anyone looking to explore the wonders of the universe. Whether you're interested in planetary observation, lunar details, or deep-sky wonders, this telescope offers the tools necessary to make your astronomical explorations rewarding.
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