Looking Back, Looking Forward

  • Neil English
Part of the Patrick Moore's Practical Astronomy Series book series (PATRICKMOORE)


Refractors are the royalty of telescopes. Their amazing variety of form and function is truly astonishing, reflecting, no doubt, the great popularity they enjoy with amateur astronomers, birders, and collectors alike. As we’ve seen, purchasing a good all-around refractor will not break the bank, and even a modest investment will secure an instrument that will serve up a lifetime of great views. The biggest change in recent years, of course, is the proliferation of low-cost Apo models using synthetic ED glass. A century ago, the keen amateur astronomer had a long focus instrument with an uncoated lens, typically an F/15, in apertures ranging from 3 to 6 in. Although a 3-in. instrument was affordable (after saving for some time, perhaps) to the average working man, 6-in. instruments were prohibitively expensive to all but the most wealthy of individuals.


Focal Length Spherical Aberration Chromatic Aberration Color Correction Double Star 
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Copyright information

© Springer Science+Business Media, LLC 2011

Authors and Affiliations

  1. 1.GlasgowUK

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