Books by Philip S. Harrington

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Astronomy For All Ages

The Deep Sky: An Introduction


The Illustrated Timeline of the Universe

The Space Shuttle

Star Ware, 4th edition

Star Watch

Touring the Universe Through Binoculars


Star Ware

Chapter 6.     The "Eyes" Have It

Topics covered On-line Bonus Material Recommended reading

Topics covered

  • Image Acrobatics 

    • Eyepiece aberrations

  • Eyepiece Evaluation

    • Huygens

    • Ramsden

    • Kellner

    • RKE

    • Orthoscopic (Abbe)

    • Erfle

    • Plössl

      • Super Plössl

    • Super-deluxe-extra-omni-ultra-maxi-mega-colossal eyepieces

    • No-frills eyepieces

    • Zoom eyepieces

    • Barlow lenses

    • Focal reducers

    • Coma correctors

    • Reticle eyepieces

  • Pieces of the Puzzle

On-line Bonus Material

Recommended reading


    Web sites

  • Affordable Astronomy Equipment Reviews

    • A new, but up and coming web site of astronomical equipment reviews.

  • All About Eyepiece Designs

    • Nice overview of basic eyepiece designs.

  • Excelsis Rate Your Equipment

    • An interesting on-line poll that asks visitors to rate their telescopes, binoculars, eyepieces, and other equipment.  Don't take all of the remarks seriously, however.


    • Ed Ting's excellent site devoted to reviews of telescopes and accessories.

  • Telescope Simulator

    • Change telescope and eyepiece parameters, and this web site by Matt Wier will show what several objects will look like.  Very good test to see how a new eyepiece will work in your telescope. 

  • telescope reviews

    • Todd Gross's extensive collection of telescope, binocular, and eyepiece reviews by Boston's premier television meteorologist and others.