Celestron 80 manual Transparency, Sky Illumination, Seeing

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Observing Deep-Sky Objects

Deep-sky objects are simply those objects outside the boundaries of our solar system. They include star clusters, planetary nebulae, diffuse nebulae, double stars and other galaxies outside our own Milky Way. Unlike the sun, moon and our five major planets, most deep-sky objects are not visible to the naked eye. Finding them requires a method called star hopping. Celestron Sky Maps (#93722) can help you locate the brightest deep-sky objects.

Most deep-sky objects have a large angular size. Therefore, a low-to-moderate power eyepiece is all you need to see them. Visually, they are too faint to reveal any of the color seen in long exposure photographs. Instead, they appear black and white. Because of their low surface brightness, they should be observed from a “dark-sky” location. Light pollution around large urban areas washes out most nebulae making them difficult, if not impossible, to observe.

“Seeing” Conditions

Viewing conditions affect what you can see through your telescope during an observing session. Conditions include transparency, sky illumination and “seeing”. Understanding viewing conditions and the affect they have on observing will help you get the most out of your telescope.

Transparency

Transparency refers to the clarity of the atmosphere and is affected by clouds, moisture, dust and other airborne particles. Thick cumulus clouds are completely opaque, while cirrus clouds can be thin, allowing light from the brightest stars through. Hazy skies absorb more light than clear skies, making fainter objects hard to see and reducing contrast on brighter objects. Dust particles and gases ejected into the upper atmosphere from volcanic eruptions also affect transparency. Ideal conditions are when the night sky is inky black.

Sky Illumination

General sky brightening caused by the moon, aurorae, natural airglow and light pollution greatly affect transparency. While not a problem when viewing brighter stars and planets, bright skies reduce the contrast of extended nebulae, making them difficult, if not impossible, to see. To maximize your observing, limit deep-sky viewing to moonless nights, far from the light polluted skies found around major urban areas. Light Pollution Reduction (LPR) filters enhance deep-sky viewing from light polluted areas by blocking unwanted light, while transmitting light from certain deep-sky objects. Planets and stars can still be observed from light pollued areas or when the moon is out.

"Seeing"

The terms “seeing conditions” or “seeing” refer to the stability of the atmosphere, which directly effects the amount of fine detail seen in extended objects. Essentially, extended objects are objects other than stars, of some size, such as nebulae and galaxies.

The air in our atmosphere acts as a lens, which bends and distorts incoming light rays. The amount of bending depends on air density. Varying temperature layers have different densities and, therefore, bend light differently. Light rays from the same object arrive slightly displaced, creating an imperfect or smeared image. These atmospheric disturbances vary from time-to-time and place-to-place. Another form of turbulence that affects seeing conditions is referred to as “air parcels”. These air parcels are the smaller turbulence patterns in the air, within your immediate environment. The size of the air parcels, compared to the aperture of your telescope, also determines seeing quality. Under good seeing conditions, fine detail is visible on the brighter planets like Jupiter and Mars, and stars are pinpoint images. Under poor seeing conditions, images are blurred and star images are diffuse. Seeing conditions are rated on a five-point scale with one being the worst

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Contents Powerseeker 80 EQ Telescope PowerSeeker 80EQ Refractor PowerSeeker 80EQ Identifying Parts of Your FirstscopeAssembling Your Telescope Telescope Operation  Using Your Telescope Balancing the Telescope in Declination DEC Image OrientationBalancing the Telescope in Right Ascension R.A Focusing Celestial Coordinate SystemMotion of the Stars Latitude ScalesPointing at Polaris Using the Setting Circles Finding the North Celestial PoleMagnification Power Page Lunar Observing Hint Celestial ObservingObserving the Moon Observing the PlanetsSeeing TransparencySky Illumination Telescope Maintenance Optional Accessories #21048Series 3 #94119-30 Series 1 #94119-10Series 2 #94119-20 Series 4 #94119-40Celestron TWO Year Warranty Celestron

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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