Terrestrial Photography
Your NexStar 8i makes an excellent 2000mm telephoto lens for terrestrial (land) photography (The NexStar 5i would be equivalent to a 1250mm lens). Terrestrial photography is best done will the telescope in
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-
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
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.
CCD Imaging
CCD Imaging is the most challenging form of astro photography and involves the use of a CCD (Charged Coupled Device) camera attached to the telescope at prime focus. The benefits of CCD imaging is the extreme light sensitivity of the electronic chip inside the camera. This allows you to record much fainter detail in a shorter period of time than would be possible with film photography. Due to the relative small size of the CCD chip, the field of view when imaging will be less than the field of view of a film camera. Using Celestron's optional f/6.3 Reducer/Corrector accessory in conjunction with a CCD camera (or film camera) will greatly increase the photographic field of view and will make finding and tracking a celestial object much easier.
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