Atmospheric dispersion corrector

Atmospheric dispersion corrector

A new corrector for atmospheric dispersion. Now some will say, it's been around for a long time... yes, but this is one of the few on the market that uses plane-parallel cemented wedge plates and thus delivers diffraction-limited images. Due to the specially matched glass types, the corrector is free of image offset and thus free of coma. This is the only way your telescope can develop its full performance potential.

Technical data:
  • Overall length: 35mm
  • Connection thread: T2 (M42x0.75) on both sides
  • Transmission: 17 mm
  • Broadband AR coating: 340-900nm
  • Surface accuracy: Better ?/10 at 633 nm
Manufacturer : APM
SKU : ADK
Price: 1625.00 € incl tax 19% (Germany)
Delivery date : 3-4 days
Product description
The dispersion corrector is a component that corrects the refraction of light in the atmosphere. Simply explained, you often see colour fringes on bright low objects when observing with the telescope. Large or bright objects such as Jupiter, Venus and Sirius have a red and blue colour fringe and also appear distorted near the horizon. This effect is caused by the refraction of light in the atmosphere and is called atmospheric dispersion. The atmosphere acts like a prism here and fans out the incoming light beam into its spectral components. This effect is stronger the lower the object is above the horizon.

Using the ADK is very simple. With the multi-function dial, both the direction of the dispersion (zenith) and the strength of the correction can be set. In the zero position of the dispersion, a small mechanical detent can be felt. This makes it very easy to find the neutral position. The maximum correction is reached after one turn. After a further turn, there is again no correction in the neutral position. If you continue to turn, the maximum correction in the opposite direction is reached after one turn and the initial position after another turn. The adjusting wheel must always point in the direction of dispersion.

The special feature of this model:

- Lenses are made of quartz

- No image shift

- No axis coma or astigmatism

- 100% made in Germany

Technical data:
  • Overall length: 35mm
  • Connection thread: T2 (M42x0.75) on both sides
  • Transmission: 17 mm
  • Broadband AR coating: 340-900nm
  • Surface accuracy: Better then Lambda/10 at 633 nm


Scope of delivery:
  • Corrector in bag
Products specifications
Lenght35mm
surface accuracyBetter λ/10 at 633 nm
Unobstructed diameter17mm
Connectingthreadon both sides T2 (M42x0,75)
CoatingAR-couting: 340-900nm

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