SV199 1.25-inch Atmospheric Dispersion Corrector

Surface Accuracy: 1/4λBroadband Anti-reflection Coated BK7 Deviation Range: 4.5°Built-in Spirit Level Co-axial Locked Mount The light from stars and planets is refracted by the layer of air when it passes through the Earth's atmosphere and this causes irritating colour fringing on the edges of planetary discs. The ADC corrects the dispersive effects of earth’s atmosphere. You will get sharper images of planets and moon.The ADC lets you observe planets with high brilliance and colour and without chromatic aberration when they are close to the horizon. Moreover the ADC frees your choice of observing time.

Improving Image Resolution

A correctly adjusted ADC will reduce this spectral spread, improving image resolution as a result. It does this by applying the opposite amount of dispersion to that caused by the atmosphere, reconverging the light of the different wavelengths at the focal plane.

1/4λ BK7 Prisms

The ADC consists of 2-high-quality minimum 1/4λ BK7 prisms that can rotate relative to each other. The prisms produce a certain extent of own chromatic aberration themselves, which is opposite to the atmospheric dispersion and that compensate for the atmospheric dispersion by putting all the rays together. The relative position of the prisms can be freely adjusted via a small slide.The broadband antireflection coatings ensure the ADC has very high light transmittance. The coating is optimized for the range of 300 to 700nm - specifically for astrophotography.

Deviation Angle: 4.5°

The ADC deviation angle is 4.5°, more than on other models. You can adjust the chromatic aberration via the two levers to correct the atmospheric dispersion , especially when the object is close to the horizon.

Spirit Level

Before you are about to find targets, this spirit level should be fitted, then the ADC is horizontal against the horizon.And the rotatable ring scale is good for the two levers being in the relative position and you can quickly find the optimal setting for next time’s observing.

Coaxial Lock

When mounting with eyepiece or astronomy camera, this coaxial lock ensures ensure the system coaxial. And rotate the ring to tight the eyepiece or camera.

Product Structure

1.25 T Barrel : For mounting with telescope;Eyepiece Mount: 1.25” interface for mounting with eyepiece; M42*0.75 male threads for mounting with cameras;

1.25” Accessory Collar/ Coaxial LockM42*0.75 MalePrism HandleSpirit LevelAngle Ring Lock Thumbscrews1.25” barrel

How to use it?

Specification:

1.Brand: SVBONY2.Model: SV1993.Surface Accuracy: 1/4λ4.Camera / eyepiece side: 1.25" barrel + T2 male5.Telescope side: 1.25" barrel 6.Optical Aperture: 24mm usable7.Substrate: Bk78.Lateral Surface: Blackened for improved contrast9.Coatings: Anti-Reflective Broad-Band (300nm- 700nm)10.Deviation Angle: 4.5°11.Required back-focus: 56.57mm12.Net Weight: 167g

Package Includes:

1 x SV199 1.25" Atmospheric Dispersion Corrector1 x Manual

Buyers show

Author:@star.hunterEquipment:-Celestron NexStar 8 SE telescope-Extender tube-long Barlow lens cell 2x-Svbony ADC-Extender tube-QHY ir-cut filter-QHY5III462C camera.