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Orion 80 ED Refractor


Premium refractors demonstrate what the best in optical performance can be. Stars focus into perfect pinpoints, and planetary details are visible with the highest possible contrast. Achromatic refractors sacrifice much of these benefits to chromatic aberration. Apochromatic refractors, or APOs, seek absolute optical perfection with no regard to the cost of the instrument. ED refractors, such as the Orion 80ED, offer an appealing compromise, providing a near apochromatic experience at typically half of the cost.


Item #ProductStock StatusPriceShipping
09895Orion 80mm ED Refractor
Normally Ships in 7-10 Days
$499.95
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Orion 80 ED APO Refractor

Orion 80mm ED: The Refractor That Started a Revolution in Affordable ED Optics

Its fully multi-coated 80mm objective doublet contains one element crafted from extra-low-dispersion glass. Images are virtually free of chromatic aberration! With a focal length of 600mm (f/7.5), the "ED80" is wonderfully suited for visual applications on both solar system and deep-sky objects as well as for prime-focus astrophotography and CCD imaging.

Sold as optical tube assembly only, without accessories. Finished in gunmetal gray metallic enamel. Compatible tube rings are #7371, sold separately. One-year limited warranty.

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Optical Specifications: Orion 80 ED APO Refractor
Type ED Achromatic Refractor
Lens Cell Type Air Spaced Doublet
Aperture (mm) 80 mm
Aperture (in.) 3.1 inches
Focal Length 600 mm
Focal Ratio f/7.5
Magnification (w/supplied eyepiece) n/a
Limiting Visual Stellar Magnitude <p><b>Limiting Stellar Magnitude</b><br /> This is a measure of the faintest star that can be seen with a telescope under ideal conditions. We include this figure for the purpose of comparing two telescopes of different apertures using a consistent scale. Many manufactures publish this specification. Unfortunately manufactures use different methods to calculate this figure, rendering the numbers useless for direct head to head comparison of different brands of telescopes. </p> <p>Limiting stellar magnitude is the sum of the naked eye limiting magnitude and the telescopic gain. The naked eye limiting magnitude varies by location due to local light pollution; therefore, it is an assumption. This figure could be 6.5 or higher at some of the darkest locations, but less than 2 in the middle of a large city. Our calculations assume a figure of 5, which one might typically find 30-40 miles from a major urban area. </p> <p>Telescopic gain is a direct function of aperture. No attempt has been made to compensate for the affects of central obstructions or different types of optical coatings.</p> 12.1 Magnitude
Accessories and Features
Included Eyepiece(s) None
Finder None
Focuser Two-inch Crayford
Star Diagonal None
Physical Parameters
Weight, Optical Tube 5.7 Pounds
Optical Tube Length 23.5 Inches
Eyepiece Calculator
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Exit Pupil: <p>Exit pupil represents the diameter of the column of light exiting the eyepiece. Magnification is simply the ratio of telescope aperture to exit pupil. Fox example, using a telescope with 100mm aperture and an exit pupil of 2mm yields a magnification of 50X.</p> <p>There are both upper and lower limits to the useful range of exit pupils. The typical human eye pupil dilates to a maximum of 7mm when fully dark adapted. This figure decreases with age. Using an exit pupil that is larger than this upper limit simply spills the light onto an area of the eye not capable of receiving data. At the opposite end of the range, a smaller exit pupil means less area on the eye is collecting data. Images brightness decreases with decreasing exit pupil. Deep space objects grow dimmer rapidly as the exit pupil falls below 1 mm. The planets also start to become noticeably dimmer when the exit pupil falls much below 0.5 mm.</p> <p>Our eyepiece calculator provides warnings and error messages based upon the value of the exit pupil. These are intended to be guidelines as opposed to hard rules. There is no harm in violating these gidelines, but your enjoyment of the telescope may be diminished if you do. </p>