2.The declination setting circle is factory set and should not need any adjustment if it reads accurately.

3.The right ascension setting circle (#10) must be aligned. Choose a bright and easy to find star in a star chart and note the coordinates (right ascension and declination). Find the star in the finderscope and then in the telescope. Now, rotate the right ascension circle to match the coordinates of the star with the indicator mark. If you polar aligned the telescope accurately, the declination circle should be correctly set to the proper coordinates.

You may notice that there are two sets of numbers on the right ascension dial, one for the northern hemisphere

Note and one for the southern. Observers in the northern hemisphere should use the upper set of numbers while southern observers should use the lower set of numbers. Remember in the northern hemisphere, the right ascension should decrease as the telescope is moved towards the west.

4.The right ascension setting circle does not move as the telescope moves in right ascension and thus it must by aligned each time you want to use it to find a new object. However, you do not need to use a bright star each time but you can use the object you are currently observing.

5.Now, using a star chart or atlas you can find numerous objects. First move the telescope in declination to the correct declination coordinate. Then move the telescope in right ascension until the indicator points to the correct coordinate.

6.After moving the telescope to the correct celestial coordinates, look through the lower power eyepiece to see if you have located the object you wish to view. Center the object in eyepiece. If the object is not visible in the eyepiece, gradually pan the telescope, using the right ascension and declination cables, until the object is visible. Always start by using your lowest power eyepiece (20mm) then switching to higher power once you have found the desired object.

MAGNIFICATION (POWER)

The magnification (or power) of a telescope is variable depending upon the focal length of the eyepiece being used along with the focal length of the telescope. In equation format, the formula looks like this:

Magnification = FL(telescope)

FL(eyepiece)

To determine the magnification using the standard 20mm eyepiece, simply divide the focal length of your telescope by the focal length of the eyepiece (20mm). For example, dividing the focal length of the Firstscope 80 (900mm) by 20mm yields a magnification of 45 power.

Magnification through the telescope has its limits. These limits are determined by the laws of optics and the nature of the human eye. The maximum usable power is equal to 60 times the aperture of the telescope (in inches). For example, using the 80mm model (3.1") then your maximum useful power is 188x (3.1" x 60). You can create power higher than this limit but the images will be dark and blurred with poor contrast.

The maximum power is used only under ideal conditions which are not common. Most of your viewing will be done in the range of 25x to 120x. Higher powers are used mainly for lunar and planetary observing under ideal seeing conditions.

Determining Field of View

Determining the field of view is important if you want to get an idea of the angular size of the object you are observing. To calculate the actual field of view, divide the apparent field of the eyepiece (supplied by the eyepiece manufacturer) by the magnification. In equation format, the formula looks like this:

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Celestron 80 manual Magnification Power
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80 specifications

The Celestron 80, commonly referred to as the Celestron Astromaster 80, is a popular choice among amateur astronomers and nature enthusiasts alike. This versatile telescope combines portability, ease of use, and impressive optical performance, making it an excellent introduction to the world of astronomy.

One of the primary features of the Celestron 80 is its 80mm aperture. This size allows for a bright and clear view of celestial objects, even in less-than-ideal conditions. The telescope employs a fully coated optical system, which enhances light transmission and improves image clarity. As a result, users can enjoy sharp, detailed views of planets, the moon, and various deep-sky objects such as star clusters and nebulae.

The design of the Celestron 80 is particularly user-friendly. The telescope is equipped with a simple alt-azimuth mount, providing both vertical and horizontal movement. This makes it easy to track objects across the night sky. The mount is also lightweight and portable, making the telescope an ideal companion for on-the-go stargazing adventures or nature observation excursions.

Another standout characteristic of the Celestron 80 is its versatility. It comes with a couple of eyepieces, allowing users to switch magnification levels to suit their viewing preferences. The included finderscope simplifies locating celestial objects, ensuring that even novice users can quickly find and observe various targets.

The Celestron 80 also showcases advancements in technology, including its sturdy, adjustable tripod that ensures stability during use. Additionally, the telescope is designed with user comfort in mind, featuring an adjustable height to accommodate various viewing positions.

For those interested in astrophotography, the Celestron 80 offers several opportunities for capturing images of the night sky. With the proper accessories, users can attach a camera to the telescope, making it a suitable option for wide-field astrophotography.

In summary, the Celestron 80 is an excellent entry-level telescope that offers a powerful combination of features, technology, and portability. Its impressive optical performance, user-friendly design, and versatility make it a favorite among both beginners and seasoned enthusiasts. Whether you wish to observe the craters of the moon or the rings of Saturn, the Celestron 80 is poised to provide an enjoyable and fulfilling viewing experience.
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