6.Find a suitable guide star in the telescope eyepiece field of view. This is relatively easy since you can search a wide area without affecting the area covered by your camera lens. If you do not have an illuminated cross hair eyepiece for guiding, simply defocus your guide star until it fills most of the field of view. This makes it easy to detect any drift.

7.Release the shutter using a cable release.

8.Monitor your guide star for the duration of the exposure making the neccessary corrections needed to keep the star centered.

Short Exposure Prime Focus Photography

Short exposure prime focus photography is the best way to begin recording celestial objects. It is done with the camera attached to the telescope without an eyepiece or camera lens in place. To attach your camera, you need the T-adapter and a T-Ring for your specific camera (i.e., Minolta, Nikon, Pentax, etc.). The

C8-N and C10-N focuser have a built-in T-adapter and are ready to accept a 35mm camera body. The T- Ring replaces the 35mm SLR camera’s normal lens. Prime focus photography allows you to capture the entire solar disk (if using the proper filter) as well as the entire lunar disk. To attach your camera to your telescope:

1Remove the eyepiece from the 1 1/4" eyepiece holder.

2Unthread the 1 1/4" eyepiece holder from the focuser assembly. This will expose the male thread of the built- in T-adapter.

3Thread the T-ring onto the exposed T-adapter threads.

4Mount your camera body onto the T-Ring the same as you would any other lens.

With your camera attached to the telescope, you are ready for prime focus photography. Start with an easy object like the Moon. Here’s how to do it:

1.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 near full, and at its brightest, slower films are more desirable. Here are some film recommendations:

•T-Max 100

•T-Max 400

•Any 100 to 400 ISO color slide film

•Fuji Super HG 400

2.Center the Moon in the field of your telescope.

3.Focus the telescope by turning the focus knob until the image is sharp.

4.Set the shutter speed to the appropriate setting (see table 7-1).

5.Trip the shutter using a cable release.

6.Advance the film and repeat the process.

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Celestron C10-N, C8-NGT manual Short Exposure Prime Focus Photography
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C10-N, C8-NGT, C8-N specifications

The Celestron C8-NGT, C8-N, and C10-N telescopes represent a range of superior astronomical instruments that cater to both novice and experienced astronomers alike. Among these, the C8-NGT combines the advanced features of a computerized telescope with the simplicity of a Newtonian design. Its 8-inch aperture allows for impressive light-gathering capability, making it ideal for observing distant galaxies, star clusters, and nebulae. The GoTo mount enhances usability, enabling users to locate celestial objects effortlessly with the push of a button.

The C8-N, also featuring an 8-inch aperture, stands out with its open tube design that provides maximum airflow and minimizes thermal issues, ensuring optimal performance. The scope is designed with user-friendly adjustments and a sturdy equatorial mount, allowing for smooth tracking of celestial objects. Its high-quality optics provide sharp images and incredible clarity, making it suitable for both planetary and deep-sky observations.

On the other hand, the C10-N is the largest in this lineup, boasting a 10-inch aperture that dramatically enhances its light-gathering ability. This larger size makes the C10-N a powerhouse for serious astronomers looking to explore fainter objects and intricate details within astronomical features. Like the C8-N, it employs a Newtonian reflector design, allowing for a compact and manageable profile, while still providing stunning visuals across a range of celestial bodies.

All three telescopes incorporate Celestron's commitment to creating durable, robust, and user-friendly systems. They utilize premium quality glass and optics, which are coated to improve light transmission and provide high-contrast images. Additionally, they are designed with ease of assembly and portability in mind, catering to astronomers who enjoy observing in various locations.

The Celestron C8-NGT, C8-N, and C10-N serve as excellent options for anyone looking to deepen their astronomical pursuits, offering a blend of advanced technology, high-quality optical performance, and user-friendly features. Whether you're a beginner eager to peer into the wonders of the universe or an experienced observer at the peak of your skills, these telescopes offer a remarkable means to expand your cosmic horizons. With precision engineering and thoughtful design, Celestron continues to be a trusted name in the world of astronomy.
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