Astronomik L-1 UV-IR Cut L-Filter - 1.25" Mounted
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Astronomik offers a range of three ultraviolet (UV) and infrared (IR) blocking filters specifically designed for the luminance channel in astrophotography. These filters help you optimize your imaging setup to achieve the sharpest, most contrast-rich images possible. The luminance channel is critical to producing a stunning final image, as it contributes the most signal. Therefore, a high-transmission filter with a broad spectral bandpass across the entire visible range is essential for maximum sensitivity and photon capture.
However, not all optical systems-or additional components such as correctors, field flatteners, or focal reducers-provide perfect color correction. Using a Luminance filter with too wide a bandpass may introduce chromatic aberration, resulting in bloated stars and more complex image processing. To solve this, Astronomik offers three distinct Luminance filters, each tailored to different levels of optical color correction:
- L-1 UV-IR Block filter: Ideal for chromatic aberration-free optical systems such as reflector telescopes, where additional lenses are only used to correct image errors, not to change the focal ratio.
- L-2 UV-IR Block filter: Suitable for APO refractors or very good doublets used with their native focal length, reflecting telescopes with focal reducers and RASA telescopes. The transmission is very close to the UV-IR blocking filters used by companies such as Canon and Nikon in their cameras.
- L-3 UV-IR Block filter: Designed for refractors and camera lenses with less-than-perfect color correction to minimize bluish halos around stars.
Each Astronomik Luminance filter is engineered with precision coatings to eliminate halos and reflections. Even with bright stars in the field, nebulae and galaxies are captured with excellent structure and maximum contrast.
Recommended for Light-Polluted Environments
For astrophotographers working under light-polluted skies, the Astronomik CLS CCD filter is a recommended alternative to traditional Luminance filters. The CLS CCD filter blocks nearly all unwanted light pollution-including high- and low-pressure sodium and mercury vapor lamp emissions-while passing approximately equal amounts of light in all three RGB channels. This results in deeper exposures with significantly reduced background noise.
Filter Size
This filter is mounted in a threaded 1.25" cell (M28.5 x 0.6 thread), compatible with most standard filter wheels and adapters. Astronomik also offers a wide selection of filter sizes, both mounted and unmounted, to fit any optical or imaging configuration.
Technical Specifications
- Glass thickness: 1mm (excluding OWB Type 3 and XT filters)
- Polished optical glass free from striae, residual stress, and bubbles
- Extremely scratch-resistant and durable multilayer coating
- Fully resistant to high humidity and aging effects
- Equipped with Astronomik MFR coating (used across RGB, UV-IR Block, and Narrowband filters)
- Parfocal with other Astronomik filters
- Diffraction-limited-does not degrade telescope resolution or contrast
- Optimized spectral transmission windows for astrophotography
- Delivered in a high-quality, long-lasting filter case
All Astronomik filters are manufactured with ultra-precise machining and polishing processes, ensuring wedge errors remain far below industry standards. This guarantees perfect parfocality and eliminates alignment issues across filter sets. Whether you use CMOS or CCD cameras, Astronomik filters offer guaranteed sharpness, contrast, and freedom from reflections and halos-allowing you to capture the finest details of stars, nebulae, and galaxies.
Every filter undergoes rigorous quality control before leaving the factory, ensuring top-tier optical performance for your imaging sessions.
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 offers a range of three ultraviolet (UV) and infrared (IR) blocking filters specifically designed for the luminance channel in astrophotography. These filters help you optimize your imaging setup to achieve the sharpest, most contrast-rich images possible. The luminance channel is critical to producing a stunning final image, as it contributes the most signal. Therefore, a high-transmission filter with a broad spectral bandpass across the entire visible range is essential for maximum sensitivity and photon capture.
However, not all optical systems-or additional components such as correctors, field flatteners, or focal reducers-provide perfect color correction. Using a Luminance filter with too wide a bandpass may introduce chromatic aberration, resulting in bloated stars and more complex image processing. To solve this, Astronomik offers three distinct Luminance filters, each tailored to different levels of optical color correction:
- L-1 UV-IR Block filter: Ideal for chromatic aberration-free optical systems such as reflector telescopes, where additional lenses are only used to correct image errors, not to change the focal ratio.
- L-2 UV-IR Block filter: Suitable for APO refractors or very good doublets used with their native focal length, reflecting telescopes with focal reducers and RASA telescopes. The transmission is very close to the UV-IR blocking filters used by companies such as Canon and Nikon in their cameras.
- L-3 UV-IR Block filter: Designed for refractors and camera lenses with less-than-perfect color correction to minimize bluish halos around stars.
Each Astronomik Luminance filter is engineered with precision coatings to eliminate halos and reflections. Even with bright stars in the field, nebulae and galaxies are captured with excellent structure and maximum contrast.
Recommended for Light-Polluted Environments
For astrophotographers working under light-polluted skies, the Astronomik CLS CCD filter is a recommended alternative to traditional Luminance filters. The CLS CCD filter blocks nearly all unwanted light pollution-including high- and low-pressure sodium and mercury vapor lamp emissions-while passing approximately equal amounts of light in all three RGB channels. This results in deeper exposures with significantly reduced background noise.
Filter Size
This filter is mounted in a threaded 1.25" cell (M28.5 x 0.6 thread), compatible with most standard filter wheels and adapters. Astronomik also offers a wide selection of filter sizes, both mounted and unmounted, to fit any optical or imaging configuration.
Technical Specifications
- Glass thickness: 1mm (excluding OWB Type 3 and XT filters)
- Polished optical glass free from striae, residual stress, and bubbles
- Extremely scratch-resistant and durable multilayer coating
- Fully resistant to high humidity and aging effects
- Equipped with Astronomik MFR coating (used across RGB, UV-IR Block, and Narrowband filters)
- Parfocal with other Astronomik filters
- Diffraction-limited-does not degrade telescope resolution or contrast
- Optimized spectral transmission windows for astrophotography
- Delivered in a high-quality, long-lasting filter case
All Astronomik filters are manufactured with ultra-precise machining and polishing processes, ensuring wedge errors remain far below industry standards. This guarantees perfect parfocality and eliminates alignment issues across filter sets. Whether you use CMOS or CCD cameras, Astronomik filters offer guaranteed sharpness, contrast, and freedom from reflections and halos-allowing you to capture the finest details of stars, nebulae, and galaxies.
Every filter undergoes rigorous quality control before leaving the factory, ensuring top-tier optical performance for your imaging sessions.
Astronomik offers a range of three ultraviolet (UV) and infrared (IR) blocking filters specifically designed for the luminance channel in astrophotography. These filters help you optimize your imaging setup to achieve the sharpest, most contrast-rich images possible. The luminance channel is critical to producing a stunning final image, as it contributes the most signal. Therefore, a high-transmission filter with a broad spectral bandpass across the entire visible range is essential for maximum sensitivity and photon capture.
However, not all optical systems-or additional components such as correctors, field flatteners, or focal reducers-provide perfect color correction. Using a Luminance filter with too wide a bandpass may introduce chromatic aberration, resulting in bloated stars and more complex image processing. To solve this, Astronomik offers three distinct Luminance filters, each tailored to different levels of optical color correction:
- L-1 UV-IR Block filter: Ideal for chromatic aberration-free optical systems such as reflector telescopes, where additional lenses are only used to correct image errors, not to change the focal ratio.
- L-2 UV-IR Block filter: Suitable for APO refractors or very good doublets used with their native focal length, reflecting telescopes with focal reducers and RASA telescopes. The transmission is very close to the UV-IR blocking filters used by companies such as Canon and Nikon in their cameras.
- L-3 UV-IR Block filter: Designed for refractors and camera lenses with less-than-perfect color correction to minimize bluish halos around stars.
Each Astronomik Luminance filter is engineered with precision coatings to eliminate halos and reflections. Even with bright stars in the field, nebulae and galaxies are captured with excellent structure and maximum contrast.
Recommended for Light-Polluted Environments
For astrophotographers working under light-polluted skies, the Astronomik CLS CCD filter is a recommended alternative to traditional Luminance filters. The CLS CCD filter blocks nearly all unwanted light pollution-including high- and low-pressure sodium and mercury vapor lamp emissions-while passing approximately equal amounts of light in all three RGB channels. This results in deeper exposures with significantly reduced background noise.
Filter Size
This filter is mounted in a threaded 1.25" cell (M28.5 x 0.6 thread), compatible with most standard filter wheels and adapters. Astronomik also offers a wide selection of filter sizes, both mounted and unmounted, to fit any optical or imaging configuration.
Technical Specifications
- Glass thickness: 1mm (excluding OWB Type 3 and XT filters)
- Polished optical glass free from striae, residual stress, and bubbles
- Extremely scratch-resistant and durable multilayer coating
- Fully resistant to high humidity and aging effects
- Equipped with Astronomik MFR coating (used across RGB, UV-IR Block, and Narrowband filters)
- Parfocal with other Astronomik filters
- Diffraction-limited-does not degrade telescope resolution or contrast
- Optimized spectral transmission windows for astrophotography
- Delivered in a high-quality, long-lasting filter case
All Astronomik filters are manufactured with ultra-precise machining and polishing processes, ensuring wedge errors remain far below industry standards. This guarantees perfect parfocality and eliminates alignment issues across filter sets. Whether you use CMOS or CCD cameras, Astronomik filters offer guaranteed sharpness, contrast, and freedom from reflections and halos-allowing you to capture the finest details of stars, nebulae, and galaxies.
Every filter undergoes rigorous quality control before leaving the factory, ensuring top-tier optical performance for your imaging sessions.
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 L-1 UV-IR Cut L-Filter - 1.25" Mounted