5.Locate the area of the sky that you want to photograph and move the telescope so that it points in that direction.

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 necessary 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 focuser has 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.

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Celestron C100ED-R, C80ED-R manual Short Exposure Prime Focus Photography
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C100ED-R, C80ED-R specifications

Celestron, a renowned name in the field of astronomy, has built a reputation for producing high-quality telescopes that are accessible to both amateur and professional astronomers alike. Among their impressive lineup are the Celestron C100ED-R and C80ED-R telescopes, both of which are crafted to enhance the observational experience through advanced optics and user-friendly features.

The Celestron C100ED-R, a 100mm refractor telescope, stands out for its premium extra-low dispersion (ED) glass, which delivers exceptional color correction and sharpness. This ED technology minimizes chromatic aberration, ensuring clearer and more colorful celestial images. The telescope boasts a focal length of 900mm, resulting in a focal ratio of f/9. This combination allows for high magnification capabilities while maintaining a wide field of view, perfect for observing both planetary details and deep-sky objects. The robust, yet lightweight design of the C100ED-R makes it highly portable, allowing for convenient stargazing sessions.

On the other hand, the C80ED-R is a 80mm refractor telescope that combines portability with performance. With its 600mm focal length and f/7.5 focal ratio, the C80ED-R is ideal for wide-field observations, making it easy to explore star clusters and large nebulae. Like its larger counterpart, the C80ED-R features ED glass, which prevents color distortion, allowing for clear and crisp images. The compact design is perfect for those who wish to travel or set up in tight spaces, ensuring that astronomy remains accessible.

Both telescopes are equipped with high-quality multi-coated optics that enhance light transmission, resulting in brighter images. Celestron's user-friendly mounting systems allow for smooth tracking of celestial objects, making it easier to follow objects as they move across the night sky. Additionally, these telescopes come with a variety of accessories, including premium eyepieces that enhance the viewing experience, and sturdy tripods that provide stable support during observations.

In summary, both the Celestron C100ED-R and C80ED-R offer exceptional features that cater to a variety of observing needs. With advanced ED optics, high-quality construction, and portability, they are ideal choices for aspiring astronomers looking to explore the wonders of the universe. Whether you're interested in planetary observation or deep-sky exploration, Celestron's C100ED-R and C80ED-R will not disappoint.
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