Astronomik City Light Suppression / Light Pollution Reduction CLS-CCD Filter - 1.25" Mounted
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The Astronomik CLS CCD filter is designed for use with cameras that are intended for astronomical use. It enhances the contrast between all deep-sky objects and the sky background, making it ideal for astrophotography under light-polluted skies.
Its wider transmission range compared to UHC filters allows a greater amount of light to pass through, resulting in less dimming of stars.
The Astronomik CLS CCD filter is optimized to block as much unwanted light as possible while allowing the maximum amount of light from the astronomical objects to pass through. It completely blocks the emission lines of artificial light sources such as streetlights (e.g. high- and low-pressure sodium (Na) and mercury (Hg) vapor lamps) as well as all lines of natural airglow.
This filter is suitable for DSLR, CMOS, and CCD cameras and can be used with telescopes or lenses with focal ratios from 1:1.8 to 1:15.
The integrated infrared (IR)-blocking layer makes it suitable for use with cameras that do not have their own IR-block filter.
Other uses
The 1.25" and 2" socket models can be used for observations from light-polluted areas. For color images of emission line objects, the Astronomik CLS CCD filter is an excellent choice for the luminance channel.
Alternatives
For cameras with a built-in IR cut 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 version 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
Due to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore 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 coating is 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.
Useful Resources
Filter Cell Specifications
D = Filter Cell Diameter = 31.2 mm / 1.23 in
T = Total Filter Height = 6.6 mm / 0.26 in
C = Filter Cell Height (Excluding Male Thread) = 4.5 mm / 0.18 in
M = Male Thread Length = 2.1 mm / 0.08 in
F = USABLE Female Filter Thread Length = Not threaded, so you cannot stack additional filters
S = Glass Substrate Thickness = 1 mm / 0.04 in
CA = Clear Aperture = 26.1 mm / 1.03 in
Other Information
- Country of Manufacture: Germany
The Astronomik CLS CCD filter is designed for use with cameras that are intended for astronomical use. It enhances the contrast between all deep-sky objects and the sky background, making it ideal for astrophotography under light-polluted skies.
Its wider transmission range compared to UHC filters allows a greater amount of light to pass through, resulting in less dimming of stars.
The Astronomik CLS CCD filter is optimized to block as much unwanted light as possible while allowing the maximum amount of light from the astronomical objects to pass through. It completely blocks the emission lines of artificial light sources such as streetlights (e.g. high- and low-pressure sodium (Na) and mercury (Hg) vapor lamps) as well as all lines of natural airglow.
This filter is suitable for DSLR, CMOS, and CCD cameras and can be used with telescopes or lenses with focal ratios from 1:1.8 to 1:15.
The integrated infrared (IR)-blocking layer makes it suitable for use with cameras that do not have their own IR-block filter.
Other uses
The 1.25" and 2" socket models can be used for observations from light-polluted areas. For color images of emission line objects, the Astronomik CLS CCD filter is an excellent choice for the luminance channel.
Alternatives
For cameras with a built-in IR cut 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 version 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
Due to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore 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 coating is 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.
The Astronomik CLS CCD filter is designed for use with cameras that are intended for astronomical use. It enhances the contrast between all deep-sky objects and the sky background, making it ideal for astrophotography under light-polluted skies.
Its wider transmission range compared to UHC filters allows a greater amount of light to pass through, resulting in less dimming of stars.
The Astronomik CLS CCD filter is optimized to block as much unwanted light as possible while allowing the maximum amount of light from the astronomical objects to pass through. It completely blocks the emission lines of artificial light sources such as streetlights (e.g. high- and low-pressure sodium (Na) and mercury (Hg) vapor lamps) as well as all lines of natural airglow.
This filter is suitable for DSLR, CMOS, and CCD cameras and can be used with telescopes or lenses with focal ratios from 1:1.8 to 1:15.
The integrated infrared (IR)-blocking layer makes it suitable for use with cameras that do not have their own IR-block filter.
Other uses
The 1.25" and 2" socket models can be used for observations from light-polluted areas. For color images of emission line objects, the Astronomik CLS CCD filter is an excellent choice for the luminance channel.
Alternatives
For cameras with a built-in IR cut 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 version 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
Due to the high-precision machining of the carrier substrate, all Astronomik filters are parfocal with wedge errors far below all common tolerances. Astronomik filters are diffraction-limited, ensuring that the optical performance (resolution and contrast) of your telescope is not compromised. Issues concerning focal distances and the exact alignment of images from each color channel are therefore 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 coating is 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.
Useful Resources
Filter Cell Specifications
D = Filter Cell Diameter = 31.2 mm / 1.23 in
T = Total Filter Height = 6.6 mm / 0.26 in
C = Filter Cell Height (Excluding Male Thread) = 4.5 mm / 0.18 in
M = Male Thread Length = 2.1 mm / 0.08 in
F = USABLE Female Filter Thread Length = Not threaded, so you cannot stack additional filters
S = Glass Substrate Thickness = 1 mm / 0.04 in
CA = Clear Aperture = 26.1 mm / 1.03 in
Other Information
- Country of Manufacture: Germany
Astronomik City Light Suppression / Light Pollution Reduction CLS-CCD Filter - 1.25" Mounted