Designers of refracting telescopes figured out, for one, that by using two different kinds of glass together in the objective lens, they could cause the red and blue ends of the spectrum to ...

It was soon realized that what was to become known as chromatic aberration was a limiting factor in refracting telescopes, and that this could be overcome by making lenses with longer focal length ...

The original instrument to occupy the 25-foot diameter dome was the 10.5-inch Bausch refracting telescope (f/15.5) installed in the brand new observatory in 1953. Bausch & Lomb Company gave the ...

These refracting telescopes were quite popular and often ... Ultimately mostly correct, he proved that lenses refract light to a focal point but that different wavelengths refract differently.

The second floor consists of the Equatorial Room which is home to the star of McKim Observatory: a Clark Refracting Telescope with a 9.53” objective lens made by the renown Alvin Clark and Sons. The ...

Save £26 on a refractor telescope that, with a 90mm aperture, a 900mm focal length and a multi-coated objective lens, offers crystal clear views of the moon and planets. The Evostar 90 EQ2 ...

This 82mm/3.2-inch refractor is one of a kind in that ... an image of the moon by holding your smartphone's camera lens up to a telescope's eyepiece, you'll know it's a tricky maneuver.