What are the best combinations of magnifying power and aperture?
Astronomers agree that useful magnification in perfect “seeing” conditions with excellent optics can never exceed 50x-60x per inch of aperture. Perfect seeing conditions are so rare that most of us will never be lucky enough to get more than 40x per inch, even with a superb instrument. Another reliable measure of the “Maximum Limiting Visual Power,” is to double the aperture in millimeters. Therefore, a top quality 60mm telescope, in “perfect seeing conditions,” may achieve 120x – not the ridiculous 250x, 375x or 450x advertised for “junk” telescopes. .
