Celestron 80GTL manual Solar Observing Hints, Observing Deep Sky Objects, Terrestrial Land Viewing

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•Sunspots: Dark regions of the sun's photosphere which are cooler than the surrounding area. Sunspots are usually

seen to consist of two parts: the inner darker core, the umbra, and the surrounding less dark region, the penumbra.

•Granulation: Small convection cells in the photosphere that appear as "rice grain" markings.

•Faculae: Large patches of bright material probably due to elevated clouds of luminous gas seen in the vicinity of sunspots.

•Limb Darkening: An observed darkening near the limb of the sun's surface compared to its brighter center due to the amount of atmospheric layers penetrated when viewing the sun's limb.

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 on GT models, be sure to select 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.

Terrestrial (Land) Viewing

Your NexStar 80GTL also makes an excellent daytime spotting scope. For daytime viewing, the 90˚ erect image diagonal must be inserted into the telescope's focuser. For correct viewing of land objects make sure the eyepiece is pointing straight up out of the diagonal. Rotating the eyepiece and diagonal to either size will cause the image to also rotate in the field of view of the eyepiece.

Terrestrial (Land) Viewing Hints

To save land objects into your hand control’s database as User Defined Objects, first complete the Quick Alignment procedure, this will bypass the normal two star alignment needed for nighttime viewing.

Since daytime land objects usually remain stationary, remember to turn off the telescopes tracking.

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

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Contents NexStar 80GTL Table of Contents Telescope Maintenance Page NexStar 80GTL Refractor Telescope NexStar 80 GTL Assembling the NexStarBalancing the Telescope tube Attaching the Telescope to the TripodErect Image Diagonal Eyepiece FocusingStar Pointer Finderscope Protective plastic cover over the battery see figure Star Pointer InstallationStar Pointer Operation Installation and Use Using your Solar FilterCleaning and Storage About the FilterPowering the NexStar Outlet Battery PackAttaching the Hand Control HandNexStar GT Hand Control Hand Control Operation Alignment ProcedureAuto-Align Hints HelpfulTwo Star Alignment NexStar Re-Alignment Quick-AlignObject Catalog Tour ModeSelecting an Object Slewing to an ObjectDirection Buttons Set Up ProceduresRate Button EQ North Alt-AzEQ South OffHint Utility FeaturesPage NexStar Ready Correct image as viewed when Using erect image diagonal FocusingGeneral Observing Hints Determining Field of ViewLunar Observing Hints Observing the MoonObserving the Planets Planetary Observing HintsObserving Deep Sky Objects Solar Observing HintsTerrestrial Land Viewing Terrestrial Land Viewing HintsSeeing Sky IlluminationCare and Cleaning of the Optics Page LPR Filter #94126A Opttiicall Speciiffiicattiion Appendix a Technical SpecificationsGlossary of Terms Page Page Communication Protocol Appendix C RS-232 ConnectionAppendix D Maps of Time Zones Page Page Page Page Page Page Page Celestron TWO Year Warranty

80GTL specifications

The Celestron 80GTL is a powerful and compact telescope designed for both amateur astronomers and experienced stargazers. It combines modern technology with user-friendly features, making it an excellent choice for those looking to explore the night sky. With its 80mm aperture, the 80GTL captures enough light to reveal a variety of celestial objects, from the moon’s craters to distant galaxies.

One of the standout characteristics of the Celestron 80GTL is its innovative Altazimuth mount. This mount provides smooth and precise movements in both horizontal and vertical directions, allowing users to easily track celestial objects as they move across the sky. The setup is quick and straightforward, making it ideal for beginners who may be intimidated by more complex mounts.

The telescope is equipped with Celestron’s StarScope system, which includes a computer-controlled GoTo mount. This feature allows users to automatically locate and track over 40,000 celestial objects with the push of a button. The included hand controller is intuitive and easy to navigate, giving users instant access to stars, planets, and deep-sky objects. This technology not only enhances the viewing experience but also helps novice astronomers learn about the universe with guided tours through the night sky.

Another notable feature of the Celestron 80GTL is its sturdy construction and lightweight design. Made from high-quality materials, it boasts durability while remaining portable for easy transport. Weighing just under 10 pounds, this telescope can be taken on camping trips or excursions, allowing users to enjoy astronomy in various locations.

Additionally, users will appreciate the 80GTL’s fully coated glass optics which provide excellent image quality and contrast. The included 25mm and 10mm eyepieces offer different magnifications, catering to diverse viewing preferences. Whether observing the rings of Saturn or the detail of lunar landscapes, the 80GTL promises clear and sharp images.

In summary, the Celestron 80GTL is a highly capable telescope, combining an accessible design with advanced technologies. Its user-friendly GoTo mount, quality optics, and lightweight build make it an exceptional option for anyone wishing to delve into the wonders of the cosmos, ensuring both enjoyment and education in the field of astronomy.