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. 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 mold called a "master block" during the polishing process. This allowed for inexpensive mass production of corrector plates of uniform shape. The telescope line had a trademark matte orange tube (changed to glossy black in 1980, and back to semi-gloss orange in 2006), and double-fork
equatorial mount, and became a popular large aperture, compact design. Other telescope product lines include the CGE, CGEM, CPC, Origin, Evolution, NexStar, Omni, Onyx, AstroMaster, Ambassador, TravelScope, StarSense Explorer and PowerSeeker product lines. These range from large computerized reflectors with GPS to decorative/casual viewing telescopes with brass tube refractors on wood mounts. Celestron products (as of 2026) include: • 5", 6", 8", 9.25", 11", and 14" Schmidt-Cassegrain telescopes (the number denoting the
aperture) on
German equatorial mounts (all) or fork mounts (all excluding C14), with most benefiting from
GoTo control. • A range of 8", 9.25", 11", and 14" modified Schmidt-Cassegrains with a more advanced optical design marketed as EdgeHD • A range of 6", 8", 11", and 36 cm Rowe-Ackermann Schmidt Astrographs (RASA) • A range of 3.5 to 7-inch (180mm)
Maksutov-Cassegrain telescopes • A range of 2 to
refractor telescopes • 4.5 to traditional
reflector telescopes on both German equatorial and Dobsonian mounts •
SkyScout – an astronomical sky finder or a personal planetarium • Digital, Biological, and Stereo viewing microscopes • Binoculars and Spotting scopes • Various mounts • Numerous
eyepiece lines, including both simple Plossl and complex wide-field designs such as the X-Cel and Luminos eyepiece lines. File:Telescope Celestron window.jpg|Celestron NexStar 114 telescope File:Celestron C8 Teleskop (freigestellt).JPG|Celestron C8 telescope File:Celestron Omni xlt120.jpg|An Omni XLT120 achromatic refractor File:Goto telescope.jpg|Celestron NexStar 130SLT Goto telescope File:Celestron Powerseeker 80eq telescope.JPG|Celestron Powerseeker model 80EQ File:Celestron FirstScope 76.jpg|FirstScope 76 tabletop
Dobsonian File:Celestron EdgeHD with solar filter.jpg|Celestron EdgeHD with solar filter File:6se.jpg|Celestron Nexstar 6SE
Schmidt-Cassegrain Telescope Celestron telescopes offer the option to use computerized location of astronomical objects as well as mounts that will aim themselves at any given object, a technology known as GoTo. Most of the computerized models can be connected to an external computer via an
RS-232 cable, allowing them to be controlled by a third-party astronomy program or connected to a
GPS receiver. GPS receivers are useful for programming the telescope with its precise location and time, which aids the alignment process required for GoTo. The Evolution and Origin series of telescopes can additionally be controlled remotely via the SkyPortal mobile application, and older mounts can utilize this function with a plug-in WiFi module. Some motorized telescopes sold during the mid 80s to early 90s that used a form of GoTo technology, such as the Celestron Compustar, did not allow for dates after 2000, making some Celestron products susceptible to the
Y2K bug. However, a third party chip to update the computer is available for some products. ==Competition with Meade==