Apochromats are refractors whose lenses are laid out in such a way as to combine at least three colours at a common focal point. This suppresses the chromatic aberration that is typical of refractor telescopes. Without this correction, bright objects like the Moon or the planets would have disruptive colour fringes.
William Optics
Apochromatic refractor AP 51/250 RedCat WIFD
$ 1,290.00
William Optics
Apochromatic refractor AP 71/350 RedCat 71 WIFD
$ 2,560.00
TS Optics
Apochromatic refractor AP 80/480 ED Triplet Photoline OTA
RRP:
$ 1,170.00
Our price:
$ 760.00
William Optics
Apochromatic refractor AP 51/178 MiniCat WIFD OTA
$ 1,400.00
Omegon
Apochromatic refractor Pro APO AP 108/600 Quintuplet OTA
$ 3,090.00
Omegon
Apochromatic refractor Pro APO AP 85/510 Triplet ED FCD-100
RRP:
$ 1,199.00
Our price:
$ 949.00
William Optics
Apochromatic refractor AP 91/448 BlackCat 91 WIFD OTA
$ 3,860.00
Skywatcher
Apochromatic refractor AP 80/600 EvoStar ED OTA
$ 930.00
Omegon
Apochromatic refractor Pro APO AP 106/700 Triplet ED FCD-100
RRP:
$ 2,090.00
Our price:
$ 1,990.00
Askar
Apochromatic refractor AP 50/200 ACL200 OTA
$ 1,060.00
Omegon
Pro APO AP 72/400 Quintuplet OTA Apochromatic refractor
$ 1,290.00
Skywatcher
Apochromatic refractor AP 72/420 EvoStar 72 ED DS Pro OTA
$ 520.00
Askar
Apochromatic refractor AP 72/400 FRA400C Astrograph
$ 1,230.00
Omegon
Apochromatic refractor Pro APO 85/560 ED Triplet CEM26 LiteRoc
RRP:
$ 3,908.00
Our price:
$ 3,890.00
Skywatcher
Apochromatic refractor AP 100/550 ESPRIT-100ED Professional OTA
RRP:
$ 2,810.00
Our price:
$ 2,530.00
Askar
Apochromatic refractor AP 40/180 FMA180PRO OTA
$ 620.00
APM
Apochromatic refractor AP 140/980 SD OTA
RRP:
$ 3,970.00
Our price:
$ 3,500.00
Explore Scientific
Apochromatic refractor AP 102/714 ED FCD-100 CF Hexafoc iEXOS-100 PMC-8 Wi-Fi GoTo
RRP:
$ 3,320.00
Our price:
$ 2,980.00
Skywatcher
Apochromatic refractor AP 120/840 ESPRIT-120ED Professional OTA
$ 4,020.00
Skywatcher
Apochromatic refractor AP 62/400 Evolux-62ED Star Adventurer GTi Wi-Fi GoTo SET
RRP:
$ 1,750.00
Our price:
$ 1,640.00
William Optics
Apochromatic refractor AP 61/300 RedCat 61 OTA
$ 2,110.00
William Optics
Apochromatic refractor AP 108/518 UltraCat WIFD
$ 4,550.00
TS Optics
Apochromatic refractor AP 60/360 PhotoLine FPL53 Red OTA
RRP:
$ 700.00
Our price:
$ 530.00
Omegon
Apochromatic refractor Pro APO AP 96/575 Triplet ED FCD-100
$ 1,490.00
Omegon
Apochromatic refractor Pro APO AP 61/360 Triplet ED OTA + Pro Reducer 0.75x
RRP:
$ 1,064.00
Our price:
$ 999.00
Omegon
Apochromatic refractor Pro APO AP 66/400 ED OTA
$ 669.00
Tecnosky
Apochromatic refractor AP 130/900 SLD OWL Triplet OTA
$ 3,980.00
ZWO
Apochromatic refractor FF65 AP 65/416 Quintuplet OTA
RRP:
$ 1,640.00
Our price:
$ 1,230.00
Omegon
Telescope Pro APO 72/400 Quintuplet CEM26 LiteRoc
RRP:
$ 3,348.00
Our price:
$ 3,290.00
Vixen
Telescope AP 80/600 ED80Sf Porta-II
$ 1,520.00
Tecnosky
Apochromatic refractor AP 125/975 OWL ED OTA
$ 2,330.00
Explore Scientific
Apochromatic refractor AP 80/480 ED FCD-100 Hexafoc OTA
$ 1,460.00
TS Optics
Apochromatic refractor AP 102/1122 ED OTA
RRP:
$ 1,170.00
Our price:
$ 1,000.00
Omegon
Apochromatic refractor Pro APO AP 110/660 ED Carbon OTA
$ 1,790.00
Tecnosky
Apochromatic refractor AP 80/480 OWL Triplet OTA
$ 1,410.00
Askar
Apochromatic refractor AP 40/180 FMA180 OTA
$ 497.00
Refractors are telescopes where the objective consist of one or more glass lenses. The lens refracts light to a focal point. However, the exact location of the focal point depends on the wavelength (colour) of the light. This causes chromatic aberration which is noticeable as a coloured fringe around bright objects. In physics, this dependence of refraction on wavelength is called dispersion.
There is no really precise definition of the term apochromat. Most apochromats have an objective consisting of two lenses, in which a special glass is deployed. This so-called ED glass has particularly low dispersion (the abbreviation ED stands for extra-low dispersion). The ED apochromats provides a largely pure-colour image.
An objective consisting of three or four lenses will provide an even sharper image. These apochromats are called triplets or quadruplets. These can be as good as mirror optics in term of colour purity.