Search results
Results from the WOW.Com Content Network
Primary lens: The objective of a refracting telescope. Primary mirror: The objective of a reflecting telescope. Corrector plate: A full aperture negative lens placed before a primary mirror designed to correct the optical aberrations of the mirror. Schmidt corrector plate: An aspheric-shaped corrector plate used in the Schmidt telescope.
Celestron was the first large scale commercial manufacturer of the Schmidt-Cassegrain telescope, introducing its "C8" 8" diameter 2032 mm focal length, ƒ10 telescope in 1970. [7] The primary innovation Celestron/Tom Johnson devised was a method to produce Schmidt corrector plates using a vacuum to pull the glass blanks into a pre-shaped curve ...
Celestron did not indicate this obsolescence date on the product or in the manual. As of April 7, 2019, the Sky Scout can no longer decode the GPS supplied date and time correctly, because of the GPS week number rollover in 2019. [2] It is possible to enter the latitude/longitude and time/date manually to continuously use the device, pending ...
A telescope on an alt-azimuth GoTo mount. Note the keypad, resting on the platform between the tripod's legs, that is the telescope's hand control. Batteries are stored in the circular compartment just above the tripod. In this picture, the compartment is just above the hand control.
When Edmund Scientific introduced the telescope in 1976 they called it "The Edmund Wide-Field Telescope" with a Part Number "2001" [5] Edmund had a public contest which ran until November 15, 1976, to come up with a name. [6] The winning name was "Astroscan 2001". The "2001" part of the name was dropped over time.
Ever since Galileo Galilei adapted a Dutch invention for astronomical use, astronomical telescope making has been an evolving discipline. Many astronomers after the time of Galileo built their own telescopes out of necessity, but the advent of amateurs in the field building telescopes for their own enjoyment and education seems to have come into prominence in the 20th century.
This is a list of United States Army fire control, and sighting material by supply catalog designation, or Standard Nomenclature List (SNL) group "F".The United States Army Ordnance Corps Supply Catalog used an alpha-numeric nomenclature system from about the mid-1920s to about 1958.
In 2007, Obsession Telescopes released a second series of telescopes more portable than their original design. They designated this series as Ultra Compact (UC), referring to their former one as 'Classic.' From 2009-2012 their telescopes ranged from USD 3000 for a 12.5 inch telescope, up to USD 12–15,000 for a 25-inch telescope.