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
Omegon
Apochromatic refractor Pro APO 85/560 ED Triplet CEM26 LiteRoc
RRP:
$ 3,908.00
Our price:
$ 3,890.00
William Optics
Apochromatic refractor AP 91/448 BlackCat 91 WIFD OTA
$ 3,850.00
William Optics
Apochromatic refractor AP 51/178 MiniCat WIFD OTA
$ 1,390.00
Omegon
Apochromatic refractor Pro APO AP 85/510 Triplet ED FCD-100
RRP:
$ 1,199.00
Our price:
$ 949.00
Skywatcher
Apochromatic refractor AP 72/420 EvoStar 72 ED DS Pro OTA
$ 520.00
Omegon
Apochromatic refractor Pro APO AP 106/700 Triplet ED FCD-100
RRP:
$ 2,090.00
Our price:
$ 1,990.00
APM
Apochromatic refractor AP 140/980 SD OTA
RRP:
$ 3,950.00
Our price:
$ 3,490.00
Explore Scientific
Apochromatic refractor AP 102/714 ED FCD-100 CF Hexafoc iEXOS-100 PMC-8 Wi-Fi GoTo
RRP:
$ 3,310.00
Our price:
$ 2,970.00
William Optics
Apochromatic refractor AP 71/350 RedCat 71 WIFD
$ 2,560.00
William Optics
Apochromatic refractor AP 61/300 RedCat 61 OTA
$ 2,100.00
William Optics
Apochromatic refractor AP 108/518 UltraCat WIFD
$ 4,540.00
Omegon
Apochromatic refractor Pro APO AP 61/360 Triplet ED OTA + Pro Reducer 0.75x
RRP:
$ 1,064.00
Our price:
$ 999.00
Askar
Apochromatic refractor AP 50/200 ACL200 OTA
$ 1,050.00
Omegon
Telescope Pro APO 72/400 Quintuplet CEM26 LiteRoc
RRP:
$ 3,348.00
Our price:
$ 3,290.00
Skywatcher
Apochromatic refractor AP 80/600 EvoStar ED OTA
$ 930.00
Omegon
Apochromatic refractor Pro APO AP 110/660 ED Carbon OTA
$ 1,790.00
Vixen
Apochromatic refractor AP 103/825 ED AX103S Sphinx SXP2 Starbook Ten GoTo
$ 10,500.00
William Optics
Apochromatic refractor Pleiades 111 AP 111/528 Astrograph OTA
$ 5,200.00
Skywatcher
Apochromatic refractor AP 62/400 Evolux-62ED Star Adventurer GTi Wi-Fi GoTo SET
RRP:
$ 1,740.00
Our price:
$ 1,630.00
TS Optics
Apochromatic refractor AP 80/480 ED Triplet Photoline OTA
RRP:
$ 1,170.00
Our price:
$ 760.00
William Optics
Apochromatic refractor AP 156/1217 Fluorostar Gray OTA
$ 11,000.00
Vixen
Apochromatic refractor AP 115/890 SD115S Sphinx SXP2 Starbook Ten GoTo
$ 9,600.00
Askar
Apochromatic refractor AP 72/400 FRA400C Astrograph
$ 1,230.00
ZWO
Apochromatic refractor FF130 AP 130/1000 Quadruplet OTA
$ 4,510.00
Omegon
Apochromatic refractor Pro APO AP 66/400 ED OTA
$ 669.00
Omegon
Apochromatic refractor Pro APO AP 66/400 ED SkyGuider Pro
RRP:
$ 1,735.00
Our price:
$ 1,379.00
Omegon
Apochromatic refractor Pro APO AP 140/910 Triplet ED FCD-100
$ 4,490.00
Vixen
Apochromatic refractor AP 80/600 ED80Sf Advanced Polaris
$ 2,380.00
Skywatcher
Apochromatic refractor AP 150/1200 EvoStar ED EQ6R GoTo
RRP:
$ 5,300.00
Our price:
$ 4,890.00
Vixen
Apochromatic refractor AP 81/625 SD81S II OTA
RRP:
$ 1,580.00
Our price:
$ 1,260.00
Askar
Apochromatic refractor AP 103/700 Triplet OTA
$ 1,560.00
Omegon
Apochromatic refractor Pro APO AP 104/650 ED OTA + 2'' Field Flattener
RRP:
$ 3,449.00
Our price:
$ 3,390.00
Askar
Apochromatic refractor AP 40/180 FMA180PRO OTA
$ 620.00
Omegon
Apochromatic refractor Pro APO AP 96/575 Triplet ED FCD-100
$ 1,490.00
OPT
Apochromatic refractor Radian AP 61/275 Raptor OTA
$ 2,440.00
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.