Astronomik CLS CCD Filters

Astronomik CLS CCD Filter

The Astronomik CLS CCD filter is ideal for astrophotography under light-polluted skies. It suppresses the distracting sky background, thereby enhancing the contrast between deep-sky objects and the background.

The Astronomik CLS CCD filter is designed for use with astronomical cameras (CMOS and CCD) and modified system and DSLR cameras and features an integrated infrared (IR) block filter.

The Astronomik CLS CCD filter largely suppresses artificial light pollution and enables high-contrast, deep images under light-polluted skies. The filter is optimized to block almost all unwanted light from high- and low-pressure sodium (Na)- and mercury (Hg)-vapor lamps, the emission maxima of LED lighting, as well as all lines of natural airglow. At the same time, it allows the maximum amount of light from the astronomical objects to pass through and enables a nearly true-color reproduction.

The Astronomik CLS CCD filter is suitable for telescopes or lenses with focal ratios from 1:1.8 to 1:15.

Other uses

• For color images from emission line objects, the Astronomik CLS CCD filter is an excellent choice for the luminance channel under light-polluted skies.

• The 1.25″- and 2″-cell models can be used for visual observations from light-polluted areas as well.

Alternatives

For cameras with an built-in IR block filter or for visual observation, the Astronomik CLS filter is a more budget-friendly option.

Suitability of the Astronomik CLS CCD filters

• CMOS and CCD photography: Very good blocking of light-pollution

• DSLR photography (original): Good, color balance is shifted but contrast is enhanced

• DSLR photography (astro-modified): Very good, color balance is close to perfect

• DSLR photography (MC-modified): Very good, color balance is close to perfect

Size of filter

Astronomik filters come in a wide range of standard sizes, both mounted and unmounted, to suit various optical setups and cameras.

This filter is a mounted filter in a threaded 1.25″ cell (M28.5 x 0.6 thread).

Technical Data

• 95% transmission at 486nm (H-beta)

• 95% transmission at 496nm (OIII)

• 95% transmission at 501nm (OIII)

• 97% transmission at 656nm (H-alpha)

• Transmission range: 450 to 520nm and 640 to 690nm

• Glass thickness: 1mm (except Astronomik OWB Type 3 and XT filters)

• Finely polished optical glass, free of any striae, residual stresses, and bubbles

• Extremely scratch-resistant and durable coating

• Completely resistant against high humidity and aging effects

• Parfocal with other Astronomik filters

• Diffraction-limited

• Optimized spectral windows

• Delivered in a high-quality, long-lasting filter box

• Made in Germany

Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Thanks to the high-precision machining of the glas substrate, all Astronomik filters are parfocal. The wedge errors are far below all common tolerances. Therefore, all issues concerning focal distances and the exact alignment of images from each color channel are effectively eliminated.

All Astronomik filters are ideal for modern cameras, including both CMOS- and CCD-based models, ensuring you capture the best possible images with your equipment. Sharpness, contrast, and the absence of any reflections and halos are guaranteed. Even with bright stars in the field of view, nebulae and galaxies will be captured with the finest structures. The Astronomik MFR and MaxFR coatings are designed for optimal performance across a wide range of focal ratios of the optics used.

Every Astronomik filter undergoes a rigorous quality control process before delivery.