 A 105mm diameter Meade ETX | |
| Telescope style | optical telescope  |
|---|---|
| Website | www |
The ETX ("Everybody's Telescope") is a line of smaller aperture telescopes (60mm to 125mm) made by Meade Instruments.
| A 105mm diameter Meade ETX | |
| Telescope style | optical telescope |
|---|---|
| Website | www |
The ETX ("Everybody's Telescope") is a line of smaller aperture telescopes (60mm to 125mm) made by Meade Instruments.
The ETX started out as a 90 mm (3-1/2") Maksutov Cassegrain telescope (first produced in 1996) and took advantage of high volume mass production and simplified optical and parts construction to open a new market for a cheap alternative to the very expensive Questar 3-1/2 Maksutov Cassegrain [1] [2] The ETX "line" has been expanded to 105 mm, and 125 mm Maksutov Cassegrains and achromatic refracting telescopes in sizes of 60 mm and 70 mm, but these two models were later replaced by an 80 mm model. The line has come to take advantage of "goto" telescope mount technology, making it very popular with amateur astronomers. [1]
The original 1996 model, now referred to as the "RA" or "classic" model, had a clockwork mechanism to track movement of the earth with an equatorial wedge, but it cannot be retrofitted for computer control. Also included were tabletop tripod legs similar to the Questar.
In January 1999, Meade introduced the ETX-EC which included electronic control of both axis through a small hand-controller. An optional #497 Autostar package was offered and would replace the simple electric controls, turning the ETX-EC into a fully computerized "goto" telescope. A "standard" #883 tripod was available as an optional accessory.
Not officially a new model but rather a package (which eventually became standard), the "AT" package included an ETX-EC telescope bundled with the #497 Autostar controller and a stronger "deluxe" #884 tripod.
Meade's UHTC (Ultra High Transmission Coating) treatment was first offered as an option on "EC" model telescopes (part of the "AT" bundle) in 2002. This coating improves light transmission by about 15%.
In October 2004, Meade announced the new ETX-PE or Premier Edition. The small right-angle finder scope was replaced on these models by a LNT (Level North Technology) module which included a level sensor, a magnetic north sensor, accelerometer, real-time clock and a frameless red-dot viewfinder. UHTC was still offered as an option. Also bundled was the PC interface cable. These Premier Edition telescopes had an image of the North American (ETX125) or Orion (ETX90) Nebulae printed on the optical tube. These scopes were assembled in Meade's new facility located in Mexico.
Final versions of the ETX-PE (after January 2007) used a revised (framed viewfinder) LNT module and Autostar controller (#497ep), made the UHTC coatings standard and went back to blue optical tubes. The mounting points for the tabletop tripod were deleted as well. Production of these final versions was in China.
Retail price of the ETX telescope has been constantly going down since its original 1996 introduction while capabilities and included accessories have increased dramatically.
Production of the ETX 105 ended in November 2009 and the ETX 125 followed suit in October 2011.
The ETX 90 and ETX 125 Observer telescopes returned with many upgrades in 2016 continuing the legacy of the ETX series for years to come.
In 2000, Meade added small 60mm and 70mm achromatic refractors to its ETX line. They were mounted on a dual fork mount similar to the larger models and included computer controls in the form of the #494 autostar.
At the time of introduction, they were some of the least expensive "goto" telescopes on the market.
Both models were replaced later by a single 80mm F/5 model.
In 2009, Meade introduced the ETX-LS, a 150mm (6 in) F/10 Schmidt-Cassegrain or ACF telescope on a very different single-fork arm. The LS include the Autostar III controller with over 100,000 objects in its database. It has a built-in CCD imager (E.C.L.P.S.) and a mini SD card reader for astrophotography. It includes audio and video descriptions of several hundred targets
An 8" version of the LS scope is also available, also F/10
Binoculars or field glasses are two telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes when viewing distant objects. Most are sized to be held using both hands, although sizes vary widely from opera glasses to large pedestal mounted military models.
Astrophotography, also known as astronomical imaging, is photography of astronomical objects, celestial events, and areas of the night sky. The first photograph of an astronomical object was taken in 1840, but it was not until the late 19th century that advances in technology allowed for detailed stellar photography. Besides being able to record the details of extended objects such as the Moon, Sun, and planets, astrophotography has the ability to image objects invisible to the human eye such as dim stars, nebulae, and galaxies. This is done by long time exposure since both film and digital cameras can accumulate and sum light photons over these long periods of time.
The Newtonian telescope, also called the Newtonian reflector or just the Newtonian, is a type of reflecting telescope invented by the English scientist Sir Isaac Newton (1642–1727), using a concave primary mirror and a flat diagonal secondary mirror. Newton's first reflecting telescope was completed in 1668 and is the earliest known functional reflecting telescope. The Newtonian telescope's simple design has made it very popular with amateur telescope makers.
An eyepiece, or ocular lens, is a type of lens that is attached to a variety of optical devices such as telescopes and microscopes. It is so named because it is usually the lens that is closest to the eye when someone looks through the device. The objective lens or mirror collects light and brings it to focus creating an image. The eyepiece is placed near the focal point of the objective to magnify this image. The amount of magnification depends on the focal length of the eyepiece.
The Meade Instruments Corporation is an American multinational company headquartered in Irvine, California, that manufactures, imports, and distributes telescopes, binoculars, spotting scopes, microscopes, CCD cameras, and telescope accessories for the consumer market. It is the world's largest manufacturer of telescopes.
A catadioptric optical system is one where refraction and reflection are combined in an optical system, usually via lenses (dioptrics) and curved mirrors (catoptrics). Catadioptric combinations are used in focusing systems such as searchlights, headlamps, early lighthouse focusing systems, optical telescopes, microscopes, and telephoto lenses. Other optical systems that use lenses and mirrors are also referred to as "catadioptric", such as surveillance catadioptric sensors.
The Maksutov is a catadioptric telescope design that combines a spherical mirror with a weakly negative meniscus lens in a design that takes advantage of all the surfaces being nearly "spherically symmetrical". The negative lens is usually full diameter and placed at the entrance pupil of the telescope. The design corrects the problems of off-axis aberrations such as coma found in reflecting telescopes while also correcting chromatic aberration. It was patented in 1941 by Russian optician Dmitri Dmitrievich Maksutov. Maksutov based his design on the idea behind the Schmidt camera of using the spherical errors of a negative lens to correct the opposite errors in a spherical primary mirror. The design is most commonly seen in a Cassegrain variation, with an integrated secondary, that can use all-spherical elements, thereby simplifying fabrication. Maksutov telescopes have been sold on the amateur market since the 1950s.
Celestron is a company based in Torrance, California, United States, that manufactures telescopes and distributes telescopes, binoculars, spotting scopes, microscopes, and accessories manufactured by its parent company, the Synta Technology Corporation of Taiwan.
The Cassegrain reflector is a combination of a primary concave mirror and a secondary convex mirror, often used in optical telescopes and radio antennas, the main characteristic being that the optical path folds back onto itself, relative to the optical system's primary mirror entrance aperture. This design puts the focal point at a convenient location behind the primary mirror and the convex secondary adds a telephoto effect creating a much longer focal length in a mechanically short system.
Questar Corporation is a company based in New Hope, Pennsylvania. It manufactures precision optical devices for consumer, industrial, aerospace, and military markets. Its telescopes produced for the consumer market are sold under the brand name "Questar".
Orion Telescopes & Binoculars is an American retail company that sells telescopes, binoculars and accessories online and in-store for astronomy and birdwatching. It was founded in 1975 and has corporate offices in Watsonville, California with a retail store in Cupertino, California. A large proportion of its products are manufactured by the Chinese company Synta for the Orion brand name. Orion Telescopes & Binoculars ships its products to the United States and over 20 other countries. Orion puts out a semi-quarterly mail-order catalog as well as email catalogs. The company is a prominent advertiser in North American astronomy magazines such as Sky & Telescope and Astronomy.
The following timeline lists the significant events in the invention and development of the telescope.
The Meade LX90 is a Schmidt-Cassegrain design of telescope made by Meade Instruments for the mid-priced commercial telescope market. It uses a similar optical system to the bigger and more expensive Meade LX200—although it lacks some useful functions like primary mirror locking. The LX90 telescopes were equipped with Autostar soon after its 1999 introduction by Meade instruments. Optical apertures included in the product line included 8 (20 cm), 10 (25 cm) and 12 (30 cm) inches on a double tine fork mount and Autostar system.
Rubinar is a Soviet lens design series developed and produced by JSC Lytkarino Plant of Optical Glass (LZOS). It is compact despite its long focal lengths.
Sky-Watcher is a commercial distribution company established in 1999 by the Synta Technology Corporation of Taiwan that markets telescopes and astronomical equipment, like mounts and eyepieces, aimed at the amateur astronomical market. The products are manufactured at Synta Taiwan's Suzhou Synta Optical Technology Co., Ltd. in Suzhou (Jiangsu), China. The brand is distributed in Canada and Europe and, in the late 2000s, extended to the USA market.
Great refractor refers to a large telescope with a lens, usually the largest refractor at an observatory with an equatorial mount. The preeminence and success of this style in observational astronomy defines an era in modern telescopy in the 19th and early 20th century. Great refractors were large refracting telescopes using achromatic lenses. They were often the largest in the world, or largest in a region. Despite typical designs having smaller apertures than reflectors, great refractors offered a number of advantages and were popular for astronomy. It was also popular to exhibit large refractors at international exhibits, and examples of this include the Trophy Telescope at the 1851 Great Exhibition, and the Yerkes Great Refractor at the 1893 World's Fair in Chicago.
The Meade LX200 is a family of commercial telescopes produced by Meade Instruments launched in 1992 with 8" (20.32 cm) and a 10" (25.4 cm) Schmidt–Cassegrain models on computerized altazimuth mounts. Two larger models, a 12" (30.48 cm) and a 16" (40.64 cm), quickly followed. The original version was later informally named the "classic" LX200 as newer upgraded versions replaced it. The first of these was the LX200GPS, which featured global positioning system electronics. A 360 mm (14 in) LX200GPS was later added to the line.
The ÇOMÜ Ulupınar Observatory (UPO) is a ground-based astronomical observatory, which was established in 2001 and formally opened on 19 May 2002. It is also known as Çanakkale Observatory or the University Observatory. The Ulupınar Observatory is part of the Çanakkale Onsekiz Mart University (ÇOMÜ) Faculty of Science and Arts.
The Ankara University Observatory (AUG), is a ground-based astronomical observatory operated by the Astronomy and Space Sciences Department at Ankara University's Faculty of Science. Established in 1959 by Dutch astronomer Egbert Adriaan Kreiken in Ahlatlıbel, Ankara. Currently, it consists of nine optical telescopes and a radio telescope, which is currently taken out of service. Old instruments are displayed in a museum at the observatory.
The Ondokuz Mayıs University Observatory is a ground-based astronomical observatory operated by the Astronomy and Space Sciences Department at Ondokuz Mayıs University's Faculty of Science. Established on June 1, 2006, it is located within the university campus at a distance of 14 km (8.7 mi) north-west of Samsun, northern Turkey. It is one of the six university observatories in the country.