Astronomik Hydrogen Beta / H-b Visual Filter - 1.25" Mounted
Stock count is accurate & shown in real time.
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
- This item is out of stock.
- Sign up for back-in-stock alerts to be notified when this item becomes available (account login required).
Contiguous US / Lower 48:
Free shipping applies to orders over $50 using our chosen carrier/method. Faster paid options are available at checkout.
Alaska, Hawaii & US Territories:
Free shipping applies to many—but not all—products. Enter your ZIP code in cart or upon checkout to confirm options and costs.
International:
International orders do not qualify for free shipping. Shipping, duties, brokerage, tariffs, and taxes are the customer’s responsibility. Some items may be restricted due to export, size, or manufacturer limitations.
The Astronomik H-beta filter is specifically designed for visual observation, particularly effective with larger aperture instruments. It allows the H-beta emission line to pass almost unobstructed while blocking the rest of the spectral range. This filter significantly enhances contrast, making observation of objects like the Horse Head Nebula feasible with telescope apertures ranging from 10" (250mm) to 12" (300mm).
For optimal use, the Astronomik H-beta filter is recommended for aperture ratios between 1:4 and 1:6.
The filter is most effective when used with telescopes of 8" (200mm) or larger, ensuring sufficient light gathering. Its high optical quality ensures that stars remain sharp, comparable to observation without any filter.
The Astronomik H-beta filter excels in enhancing the contrast between hydrogen nebulae and the sky background, crucial for visual observation even from dark sky areas. It allows for the observation of low-contrast hydrogen regions that are nearly imperceptible without filters.
Overall, the Astronomik H-beta filter is a crucial tool for deep-sky observers seeking to explore the depths of H-beta emission regions.
Suitability of the Astronomik H-beta filters
- Visual observation (dark skies): Very good, but only suitable for a few observation objects
- Visual observation (urban skies): Unsuitable
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
- Typical transmission of 97% at 486nm (H-beta)
- Transmission range: 480nm to 492nm
- Full-Width-Half Maximum (FWHM): 12nm
- 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.
Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline
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 H-beta filter is specifically designed for visual observation, particularly effective with larger aperture instruments. It allows the H-beta emission line to pass almost unobstructed while blocking the rest of the spectral range. This filter significantly enhances contrast, making observation of objects like the Horse Head Nebula feasible with telescope apertures ranging from 10" (250mm) to 12" (300mm).
For optimal use, the Astronomik H-beta filter is recommended for aperture ratios between 1:4 and 1:6.
The filter is most effective when used with telescopes of 8" (200mm) or larger, ensuring sufficient light gathering. Its high optical quality ensures that stars remain sharp, comparable to observation without any filter.
The Astronomik H-beta filter excels in enhancing the contrast between hydrogen nebulae and the sky background, crucial for visual observation even from dark sky areas. It allows for the observation of low-contrast hydrogen regions that are nearly imperceptible without filters.
Overall, the Astronomik H-beta filter is a crucial tool for deep-sky observers seeking to explore the depths of H-beta emission regions.
Suitability of the Astronomik H-beta filters
- Visual observation (dark skies): Very good, but only suitable for a few observation objects
- Visual observation (urban skies): Unsuitable
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
- Typical transmission of 97% at 486nm (H-beta)
- Transmission range: 480nm to 492nm
- Full-Width-Half Maximum (FWHM): 12nm
- 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.
Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline
The Astronomik H-beta filter is specifically designed for visual observation, particularly effective with larger aperture instruments. It allows the H-beta emission line to pass almost unobstructed while blocking the rest of the spectral range. This filter significantly enhances contrast, making observation of objects like the Horse Head Nebula feasible with telescope apertures ranging from 10" (250mm) to 12" (300mm).
For optimal use, the Astronomik H-beta filter is recommended for aperture ratios between 1:4 and 1:6.
The filter is most effective when used with telescopes of 8" (200mm) or larger, ensuring sufficient light gathering. Its high optical quality ensures that stars remain sharp, comparable to observation without any filter.
The Astronomik H-beta filter excels in enhancing the contrast between hydrogen nebulae and the sky background, crucial for visual observation even from dark sky areas. It allows for the observation of low-contrast hydrogen regions that are nearly imperceptible without filters.
Overall, the Astronomik H-beta filter is a crucial tool for deep-sky observers seeking to explore the depths of H-beta emission regions.
Suitability of the Astronomik H-beta filters
- Visual observation (dark skies): Very good, but only suitable for a few observation objects
- Visual observation (urban skies): Unsuitable
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
- Typical transmission of 97% at 486nm (H-beta)
- Transmission range: 480nm to 492nm
- Full-Width-Half Maximum (FWHM): 12nm
- 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.
Every Astronomik filter undergoes a rigorous quality control process before delivery. Additionally, each Astronomik Narrowband-Emissionline filter is measured using a high-end PerkinElmer Spectrophotometer to ensure it meets the specifications published on our website. On the back of each Narrowband-Emissionline
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 Hydrogen Beta / H-b Visual Filter - 1.25" Mounted