Baader CMOS-Optimized 4nm O-III f/2 Ultra Highspeed Filter for FCCT - 47.4mm Round Unmounted

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Baader CMOS-Optimized 4nm O-III f/2 Ultra-Highspeed Filter for FCCT # FCOIIIHSU-2U or 2961453U
- 47.4 mm (2" w/o cell) x 2 mm Baader O-III f/2 Ultra-Highspeed Filter – Premium Grade
- 4 nm FWHM recommended for extremely fast optical systems from f/1.8 to f/2.2
- Specially designed for the special filter requirements when used with extremely fast f/2 optics like the Celestron RASA astrographs
- Reflex-Blocker™ hard coated and planeoptically polished – with sealed coating edges (Life-Coat™)
- Blackened edges all around, with filter-lead-side-indicator in the form of a telescope-sided black outer rim
- Optimized for modern CMOS cameras, but likewise excellent for CCD camera technologies
Specifications:
- Net weight (kg): 0.07
- Suitable for f/ratio: f/1.8 to f/2.2
- Colour: Black
- Transmission Range: O-III
- Filter Thickness (without cell): 2 mm
- HBW (Half bandwidth): 4 nm
- CWL (Central Wavelength): 500.7 nm
- AR-Coating: Reflex-Blockerâ„¢ hard coated, planeoptically polished
- Special Features: CMOS-optimized with Life-Coatâ„¢
- Filter size: 47.4 mm (2" w/o cell)
- Filter Usage: CMOS, CCD, O-III
- Filter mounted: Unmounted
- Type of Filter: f/2 Ultra-Highspeed
- Single or Set?: Single Filter
- Filter shape: round
Life-Coatâ„¢: Limited-Lifetime-Warranty for CMOS-optimized Baader filters
A Baader Planetarium exclusive. Filters incorporating Baader Planetarium’s Life-Coat™ technology are so durable that Baader Planetarium warrants the coatings for the life of the filter. Baader Planetarium has developed Life-Coat™ using materials and processes that result in coatings which will not degrade or fail for a lifetime. Life-Coat™ coatings resist moisture, temperature extremes, and are hardened to withstand normal cleanings.
Baader Planetarium guarantees their Life-Coatâ„¢ coatings will not peel, flake or physically degrade and will withstand repeated cleaning with fine optical cleaning equipment. The Limited Lifetime Warranty applies to the original purchaser and does not cover failure from mis-use, physical damage through improper handling, or improper cleaning.
Other Information
- Country of Manufacture: Germany
- Baader Planetarium Warranty: Baader products are warranted for two years for flawless optical function (not necessarily cosmetic optical appearance).
Baader CMOS-Optimized 4nm O-III f/2 Ultra-Highspeed Filter for FCCT # FCOIIIHSU-2U or 2961453U
- 47.4 mm (2" w/o cell) x 2 mm Baader O-III f/2 Ultra-Highspeed Filter – Premium Grade
- 4 nm FWHM recommended for extremely fast optical systems from f/1.8 to f/2.2
- Specially designed for the special filter requirements when used with extremely fast f/2 optics like the Celestron RASA astrographs
- Reflex-Blocker™ hard coated and planeoptically polished – with sealed coating edges (Life-Coat™)
- Blackened edges all around, with filter-lead-side-indicator in the form of a telescope-sided black outer rim
- Optimized for modern CMOS cameras, but likewise excellent for CCD camera technologies
Specifications:
- Net weight (kg): 0.07
- Suitable for f/ratio: f/1.8 to f/2.2
- Colour: Black
- Transmission Range: O-III
- Filter Thickness (without cell): 2 mm
- HBW (Half bandwidth): 4 nm
- CWL (Central Wavelength): 500.7 nm
- AR-Coating: Reflex-Blockerâ„¢ hard coated, planeoptically polished
- Special Features: CMOS-optimized with Life-Coatâ„¢
- Filter size: 47.4 mm (2" w/o cell)
- Filter Usage: CMOS, CCD, O-III
- Filter mounted: Unmounted
- Type of Filter: f/2 Ultra-Highspeed
- Single or Set?: Single Filter
- Filter shape: round
Life-Coatâ„¢: Limited-Lifetime-Warranty for CMOS-optimized Baader filters
A Baader Planetarium exclusive. Filters incorporating Baader Planetarium’s Life-Coat™ technology are so durable that Baader Planetarium warrants the coatings for the life of the filter. Baader Planetarium has developed Life-Coat™ using materials and processes that result in coatings which will not degrade or fail for a lifetime. Life-Coat™ coatings resist moisture, temperature extremes, and are hardened to withstand normal cleanings.
Baader Planetarium guarantees their Life-Coatâ„¢ coatings will not peel, flake or physically degrade and will withstand repeated cleaning with fine optical cleaning equipment. The Limited Lifetime Warranty applies to the original purchaser and does not cover failure from mis-use, physical damage through improper handling, or improper cleaning.
Baader CMOS-Optimized 4nm O-III f/2 Ultra-Highspeed Filter for FCCT # FCOIIIHSU-2U or 2961453U
- 47.4 mm (2" w/o cell) x 2 mm Baader O-III f/2 Ultra-Highspeed Filter – Premium Grade
- 4 nm FWHM recommended for extremely fast optical systems from f/1.8 to f/2.2
- Specially designed for the special filter requirements when used with extremely fast f/2 optics like the Celestron RASA astrographs
- Reflex-Blocker™ hard coated and planeoptically polished – with sealed coating edges (Life-Coat™)
- Blackened edges all around, with filter-lead-side-indicator in the form of a telescope-sided black outer rim
- Optimized for modern CMOS cameras, but likewise excellent for CCD camera technologies
Specifications:
- Net weight (kg): 0.07
- Suitable for f/ratio: f/1.8 to f/2.2
- Colour: Black
- Transmission Range: O-III
- Filter Thickness (without cell): 2 mm
- HBW (Half bandwidth): 4 nm
- CWL (Central Wavelength): 500.7 nm
- AR-Coating: Reflex-Blockerâ„¢ hard coated, planeoptically polished
- Special Features: CMOS-optimized with Life-Coatâ„¢
- Filter size: 47.4 mm (2" w/o cell)
- Filter Usage: CMOS, CCD, O-III
- Filter mounted: Unmounted
- Type of Filter: f/2 Ultra-Highspeed
- Single or Set?: Single Filter
- Filter shape: round
Life-Coatâ„¢: Limited-Lifetime-Warranty for CMOS-optimized Baader filters
A Baader Planetarium exclusive. Filters incorporating Baader Planetarium’s Life-Coat™ technology are so durable that Baader Planetarium warrants the coatings for the life of the filter. Baader Planetarium has developed Life-Coat™ using materials and processes that result in coatings which will not degrade or fail for a lifetime. Life-Coat™ coatings resist moisture, temperature extremes, and are hardened to withstand normal cleanings.
Baader Planetarium guarantees their Life-Coatâ„¢ coatings will not peel, flake or physically degrade and will withstand repeated cleaning with fine optical cleaning equipment. The Limited Lifetime Warranty applies to the original purchaser and does not cover failure from mis-use, physical damage through improper handling, or improper cleaning.
Other Information
- Country of Manufacture: Germany
- Baader Planetarium Warranty: Baader products are warranted for two years for flawless optical function (not necessarily cosmetic optical appearance).

Baader CMOS-Optimized 4nm O-III f/2 Ultra Highspeed Filter for FCCT - 47.4mm Round Unmounted
