Celestron C80ED-R, C100ED-R Solar Observing Hints, Observing Deep Sky Objects, Seeing Conditions

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For safe solar viewing, use a solar filter that reduces the intensity of the Sun's light, making it safe to view. With a filter you can see sunspots as they move across the solar disk and faculae, which are bright patches seen near the Sun's edge.

Solar Observing Hints

The best time to observe the Sun is in the early morning or late afternoon when the air is cooler.

To center the Sun without looking into the eyepiece, watch the shadow of the telescope tube until it forms a circular shadow.

To ensure accurate tracking, be sure to select the solar tracking rate.

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. Most deep-sky objects have a large angular size. Therefore, low-to-moderate power 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. And, 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. Light Pollution Reduction filters help reduce the background sky brightness, thus increasing contrast.

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 effect they have on observing will help you get the most out of your telescope.

Transparency

Transparency is the clarity of the atmosphere which is affected by clouds, moisture, and other airborne particles. Thick cumulus clouds are completely opaque while cirrus can be thin, allowing the light from the brightest stars through. Hazy skies absorb more light than clear skies making fainter objects harder to see and reducing contrast on brighter objects. Aerosols 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 for the 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. LPR filters enhance deep sky viewing from light polluted areas by blocking unwanted light while transmitting light from certain deep sky objects. You can, on the other hand, observe planets and stars from light polluted areas or when the Moon is out.

Seeing

Seeing conditions refers to the stability of the atmosphere and directly affects the amount of fine detail seen in extended objects. 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

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Contents Advanced Series Advanced Series GT Introduction Care and Cleaning of the Optics Page Advanced GT Series Setting up the Tripod Attaching the Equatorial MountInstalling the Counterweight Bar Attaching the Center Leg BraceFor Non-GT Models Only Installing the CounterweightAttaching the Hand Control Holder Advanced GT Models Only Attaching the Telescope Tube to the Mount Installing the Finderscope Optical TubeInstalling the Eyepieces Balancing the Tube in R.AAdjusting the Mount Balancing the Telescope in DECAttaching the Declination Cable For GT Models Only Adjusting the Mount in AltitudeAdjusting the Mount in Azimuth Powering the Telescope Advanced GT Hand Control Hand Control Operation Double StarsAlignment Procedures Startup ProcedureAuto Align Auto Three-Star AlignRe-Alignment Quick-AlignLast Alignment Slewing to an Object Object CatalogSelecting an Object Finding PlanetsDirection Buttons Tour ModeConstellation Tour Rate ButtonSetup Procedures Identify Scope Setup Features Precise GoToObserving Tip Helpful Hint Utility Features Helpful Hint Advanced GT Image Orientation Calculating Magnification FocusingAligning the Finderscope Determining Field of View General Observing HintsCelestial Coordinate System Motion of the Stars Pointing at Polaris Finding the North Celestial Pole DefinitionDeclination Drift Method of Polar Alignment Observing the Planets Observing the MoonLunar Observing Hints Observing the SunSeeing Conditions Solar Observing HintsObserving Deep Sky Objects TransparencyPage Piggyback Short Exposure Prime Focus Photography Reducing Vibration Terrestrial PhotographyMetering Auto Guiding Care and Cleaning of the Optics Page Page Appendix a Technical Specifications Appendix B Glossary of Terms Page Eclipsing or obscuring the brightness of the star Appendix C Longitudes Latitudes Georgia Minnesota Rhode Island Canada Appendix D RS-232 Connection Additional RS232 Commands Appendix E Maps of Time Zones Page Page Page Page Page Page Page Celestron TWO Year Warranty

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.