Astronomik IR Cut Filter - 31mm Round Unmounted
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The Astronomik infrared (IR)-Block filter is the standard filter for lunar and planetary imaging with IR sensitive cameras, blocking IR-light while preserving the visible spectrum. By placing this filter in front of your camera, you can eliminate problems such as halos around objects and achieve a sharper overall image. The Astronomik IR-Block filter effectively blocks IR-light across all focal ratios.
Blocking IR-light prevents ghost images. Optical systems typically corrected for the visible spectrum can have different focal points for visible and IR-light, resulting in a blurred ghost image in addition to the intended image. Since many cameras for imaging solar system objects are sensitive to IR-light, blocking it is critical to prevent this ghosting effect.
Additionally, the Astronomik IR-Block filter acts as protection against dust particles and airborne contaminants for telescopes and cameras.
Other uses
It is an alternative to the Astronomik UV-IR Block filter if your camera has low sensitivity to UV-light.
Alternatives
Use the Astronomik UV-IR Block filter if your camera has high sensitivity to UV-light.
Suitability of the Astronomik IR-Block filter
- Visual observation: Suitable for dust protection only
- Webcam and video (planets): Very good
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 filter with a protective ring for filter wheels without screw thread. The glass thickness is 1mm, the mechanical thickness is 3mm, the diameter is 31mm.
Technical Data
- Suitable for all focal ratios
- Typical transmission: 97-99%
- Glass thickness: 1mm
- 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
Unlike other filter manufacturers, Astronomik mounts their round filters in unthreaded cells.
D = Filter Cell Diameter = 31 mm / 1.22 in
T = Total Filter/Cell Height = 3.5 mm / 0.14 in
S = Glass Substrate Thickness = 1 mm / 0.04 in
CA = Clear Aperture = 27.7 mm / 1.09 in
Other Information
- Country of Manufacture: Germany
The Astronomik infrared (IR)-Block filter is the standard filter for lunar and planetary imaging with IR sensitive cameras, blocking IR-light while preserving the visible spectrum. By placing this filter in front of your camera, you can eliminate problems such as halos around objects and achieve a sharper overall image. The Astronomik IR-Block filter effectively blocks IR-light across all focal ratios.
Blocking IR-light prevents ghost images. Optical systems typically corrected for the visible spectrum can have different focal points for visible and IR-light, resulting in a blurred ghost image in addition to the intended image. Since many cameras for imaging solar system objects are sensitive to IR-light, blocking it is critical to prevent this ghosting effect.
Additionally, the Astronomik IR-Block filter acts as protection against dust particles and airborne contaminants for telescopes and cameras.
Other uses
It is an alternative to the Astronomik UV-IR Block filter if your camera has low sensitivity to UV-light.
Alternatives
Use the Astronomik UV-IR Block filter if your camera has high sensitivity to UV-light.
Suitability of the Astronomik IR-Block filter
- Visual observation: Suitable for dust protection only
- Webcam and video (planets): Very good
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 filter with a protective ring for filter wheels without screw thread. The glass thickness is 1mm, the mechanical thickness is 3mm, the diameter is 31mm.
Technical Data
- Suitable for all focal ratios
- Typical transmission: 97-99%
- Glass thickness: 1mm
- 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 infrared (IR)-Block filter is the standard filter for lunar and planetary imaging with IR sensitive cameras, blocking IR-light while preserving the visible spectrum. By placing this filter in front of your camera, you can eliminate problems such as halos around objects and achieve a sharper overall image. The Astronomik IR-Block filter effectively blocks IR-light across all focal ratios.
Blocking IR-light prevents ghost images. Optical systems typically corrected for the visible spectrum can have different focal points for visible and IR-light, resulting in a blurred ghost image in addition to the intended image. Since many cameras for imaging solar system objects are sensitive to IR-light, blocking it is critical to prevent this ghosting effect.
Additionally, the Astronomik IR-Block filter acts as protection against dust particles and airborne contaminants for telescopes and cameras.
Other uses
It is an alternative to the Astronomik UV-IR Block filter if your camera has low sensitivity to UV-light.
Alternatives
Use the Astronomik UV-IR Block filter if your camera has high sensitivity to UV-light.
Suitability of the Astronomik IR-Block filter
- Visual observation: Suitable for dust protection only
- Webcam and video (planets): Very good
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 filter with a protective ring for filter wheels without screw thread. The glass thickness is 1mm, the mechanical thickness is 3mm, the diameter is 31mm.
Technical Data
- Suitable for all focal ratios
- Typical transmission: 97-99%
- Glass thickness: 1mm
- 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
Unlike other filter manufacturers, Astronomik mounts their round filters in unthreaded cells.
D = Filter Cell Diameter = 31 mm / 1.22 in
T = Total Filter/Cell Height = 3.5 mm / 0.14 in
S = Glass Substrate Thickness = 1 mm / 0.04 in
CA = Clear Aperture = 27.7 mm / 1.09 in
Other Information
- Country of Manufacture: Germany
Astronomik IR Cut Filter - 31mm Round Unmounted