Chroma SII (3nm) Imaging Filter - 36mm Round Unmounted
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- Engineered for deep-sky CCD & CMOS astrophotography.
- S-II 36 mm unmouted filter for compatability with a wide array of filter wheels.
- Parfocal for systems f/4.0 or slower.
Chroma S-II Filter for Finer Nebulosity Detail
The Chroma S-II filter is engineered specifically for serious deep-sky CCD and CMOS imaging, delivering exceptional optical precision and reliability in one premium package. Isolating the spectral emission of singly ionized sulfur atoms, common in nebulae, minimize light pollution noise and pull out fine nebulous detail otherwise washed out. Crafted using single-substrate glass with Chroma’s durable sputtered hard coatings, eliminating the need for laminations and ensuring long-term performance. Primary filter coatings are applied to the front surface, with anti-reflection coatings on the rear to suppress ghosting and maximize light transmission for cleaner, higher-contrast images. Designed for consistency in the field, the precisely controlled bandpasses remain spectrally stable, resisting drift even under extreme temperature changes or humidity fluctuations—so you can count on accurate color balance and repeatable results night after night! This S-II filter will fit virtually all filter drawers/holders and wheels on the market. However, please verify this with your accessory before purchase.*
Spectral Transmission Details
| Filter | Wavelength Range | Bandpass |
|---|---|---|
| S-II | ~671.6–673.1nm | 3nm |
Cleaning, Handling, and Orientation
Handle Chroma filters by the edges only. Clean gently only if necessary. Loose particles should be removed with a bulb puffer or filtered, pressurized air cleaner. If necessary, gently wipe surface using anhydrous alcohol and lint-free lab towels. Use new surface of towel with each wipe.
- Avoid touching or wiping AR coated or metal mirror surfaces.
- Avoid handling exposed coatings with bare fingers.
Proper orientation of the filter is recommended for maximize performance. These filters should be mounted with the coated surface toward the light source and the AR-coated side towards the camera sensor. The AR-coated side can be easily identified because you can look right through the AR side into the filter. The front side, on the other hand, is highly reflective to prevent unwanted light from passing through.
About Chroma Filters
Chroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission. Highly precise and accurate, the passbands of Chroma filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with focal ratios of f/4 or slower.
Specifications
- Type: Sulfur II (S-II)
- Bandpass: 3 nm
- Shape: Round
- Mounting: Unmounted
- Size: 36 mm
- Coating yype: Durable sputtered hard coatings
- Camera side: Anti-reflection coated
- Substrate: Single-piece optical glass
- Glass thickness: 3 mm
Other Information
- Country of Manufacture: United States
Chroma S-II Filter for Finer Nebulosity Detail
The Chroma S-II filter is engineered specifically for serious deep-sky CCD and CMOS imaging, delivering exceptional optical precision and reliability in one premium package. Isolating the spectral emission of singly ionized sulfur atoms, common in nebulae, minimize light pollution noise and pull out fine nebulous detail otherwise washed out. Crafted using single-substrate glass with Chroma’s durable sputtered hard coatings, eliminating the need for laminations and ensuring long-term performance. Primary filter coatings are applied to the front surface, with anti-reflection coatings on the rear to suppress ghosting and maximize light transmission for cleaner, higher-contrast images. Designed for consistency in the field, the precisely controlled bandpasses remain spectrally stable, resisting drift even under extreme temperature changes or humidity fluctuations—so you can count on accurate color balance and repeatable results night after night! This S-II filter will fit virtually all filter drawers/holders and wheels on the market. However, please verify this with your accessory before purchase.*
Spectral Transmission Details
| Filter | Wavelength Range | Bandpass |
|---|---|---|
| S-II | ~671.6–673.1nm | 3nm |
Cleaning, Handling, and Orientation
Handle Chroma filters by the edges only. Clean gently only if necessary. Loose particles should be removed with a bulb puffer or filtered, pressurized air cleaner. If necessary, gently wipe surface using anhydrous alcohol and lint-free lab towels. Use new surface of towel with each wipe.
- Avoid touching or wiping AR coated or metal mirror surfaces.
- Avoid handling exposed coatings with bare fingers.
Proper orientation of the filter is recommended for maximize performance. These filters should be mounted with the coated surface toward the light source and the AR-coated side towards the camera sensor. The AR-coated side can be easily identified because you can look right through the AR side into the filter. The front side, on the other hand, is highly reflective to prevent unwanted light from passing through.
About Chroma Filters
Chroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission. Highly precise and accurate, the passbands of Chroma filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with focal ratios of f/4 or slower.
Specifications
- Type: Sulfur II (S-II)
- Bandpass: 3 nm
- Shape: Round
- Mounting: Unmounted
- Size: 36 mm
- Coating yype: Durable sputtered hard coatings
- Camera side: Anti-reflection coated
- Substrate: Single-piece optical glass
- Glass thickness: 3 mm
| Manufacturer | Chroma Technologies |
|---|
- 1x S-II filter - 36 mm unmounted
- Engineered for deep-sky CCD & CMOS astrophotography.
- S-II 36 mm unmouted filter for compatability with a wide array of filter wheels.
- Parfocal for systems f/4.0 or slower.
Chroma S-II Filter for Finer Nebulosity Detail
The Chroma S-II filter is engineered specifically for serious deep-sky CCD and CMOS imaging, delivering exceptional optical precision and reliability in one premium package. Isolating the spectral emission of singly ionized sulfur atoms, common in nebulae, minimize light pollution noise and pull out fine nebulous detail otherwise washed out. Crafted using single-substrate glass with Chroma’s durable sputtered hard coatings, eliminating the need for laminations and ensuring long-term performance. Primary filter coatings are applied to the front surface, with anti-reflection coatings on the rear to suppress ghosting and maximize light transmission for cleaner, higher-contrast images. Designed for consistency in the field, the precisely controlled bandpasses remain spectrally stable, resisting drift even under extreme temperature changes or humidity fluctuations—so you can count on accurate color balance and repeatable results night after night! This S-II filter will fit virtually all filter drawers/holders and wheels on the market. However, please verify this with your accessory before purchase.*
Spectral Transmission Details
| Filter | Wavelength Range | Bandpass |
|---|---|---|
| S-II | ~671.6–673.1nm | 3nm |
Cleaning, Handling, and Orientation
Handle Chroma filters by the edges only. Clean gently only if necessary. Loose particles should be removed with a bulb puffer or filtered, pressurized air cleaner. If necessary, gently wipe surface using anhydrous alcohol and lint-free lab towels. Use new surface of towel with each wipe.
- Avoid touching or wiping AR coated or metal mirror surfaces.
- Avoid handling exposed coatings with bare fingers.
Proper orientation of the filter is recommended for maximize performance. These filters should be mounted with the coated surface toward the light source and the AR-coated side towards the camera sensor. The AR-coated side can be easily identified because you can look right through the AR side into the filter. The front side, on the other hand, is highly reflective to prevent unwanted light from passing through.
About Chroma Filters
Chroma manufactures the highest quality astronomy filters with durable, sputtered hard coatings using single substrates of the best glass, eliminating the need for laminations. All primary filter coatings are applied on the front surface and anti-reflection coatings on the rear surface to prevent ghosting and to maximize transmission. Highly precise and accurate, the passbands of Chroma filters remain spectrally stable and do not drift in response to extreme temperature fluctuations or changes in humidity. All filters may be used with focal ratios of f/4 or slower.
Specifications
- Type: Sulfur II (S-II)
- Bandpass: 3 nm
- Shape: Round
- Mounting: Unmounted
- Size: 36 mm
- Coating yype: Durable sputtered hard coatings
- Camera side: Anti-reflection coated
- Substrate: Single-piece optical glass
- Glass thickness: 3 mm
Other Information
- Country of Manufacture: United States
| Manufacturer | Chroma Technologies |
|---|
- 1x S-II filter - 36 mm unmounted
