Baader CMOS-Optimized 4nm S-II f/3 Ultra-Highspeed Filter - 1.25" Mounted
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- Baader S-II f/3 Ultra-Highspeed Filter – Premium Grade
- 4 nm FWHM, recommended for extremely fast optical systems from f/2.3 to f/3.4
- Specially designed for the special filter requirements when used with fast optics
- For highest contrast even at strongest light pollution, minimizes star size, emphasizes finest nebula detail – indispensable under Bortle 9/8/7/(6) skies
- 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 black frontside outer rim
- Optimized for modern CMOS cameras, but excellent for CCD camera technologies
This new generation of Baader CMOS-filters features:
- Increased contrast
- Ever more narrow passbands
- Reflex-Blocker™ coatings, for largest ever freedom from halos, even under most adverse conditions concerning aux-optics
- FWHM on each filter category carefully designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio
- Identical filter thickness to existing standards, with utmost care for parfocality
- Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim, to additionally eliminate any reflection due to light falling onto the edge of a filter
- Each filter coated individually, with sealed coating edge (NOT cut out of a larger plate with coatings left exposed, read more)
- Life-Coat™: evermore hard coatings to enable a non-aging coating for life – even in a most adverse environment
Useful Resources
Filter Cell Specifications
D = Filter Cell Diameter = 30.9 mm / 1.21 in
T = Total Filter Height = 7.6 mm / 0.29 in
C = Filter Cell Height (Excluding Male Thread) = 5.9 mm / 0.23 in
M = Male Thread Length = 1.7 mm / 0.06 in
F = USABLE Female Filter Thread Length = 2.5 mm / 0.09 in
S = Glass Substrate Thickness = 2.0 mm / 0.07 in
CA = Clear Aperture = 26.5 mm / 1.04 in
Other Information
- Country of Manufacture: Germany
- Baader S-II f/3 Ultra-Highspeed Filter – Premium Grade
- 4 nm FWHM, recommended for extremely fast optical systems from f/2.3 to f/3.4
- Specially designed for the special filter requirements when used with fast optics
- For highest contrast even at strongest light pollution, minimizes star size, emphasizes finest nebula detail – indispensable under Bortle 9/8/7/(6) skies
- 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 black frontside outer rim
- Optimized for modern CMOS cameras, but excellent for CCD camera technologies
This new generation of Baader CMOS-filters features:
- Increased contrast
- Ever more narrow passbands
- Reflex-Blocker™ coatings, for largest ever freedom from halos, even under most adverse conditions concerning aux-optics
- FWHM on each filter category carefully designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio
- Identical filter thickness to existing standards, with utmost care for parfocality
- Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim, to additionally eliminate any reflection due to light falling onto the edge of a filter
- Each filter coated individually, with sealed coating edge (NOT cut out of a larger plate with coatings left exposed, read more)
- Life-Coat™: evermore hard coatings to enable a non-aging coating for life – even in a most adverse environment
- Baader S-II f/3 Ultra-Highspeed Filter – Premium Grade
- 4 nm FWHM, recommended for extremely fast optical systems from f/2.3 to f/3.4
- Specially designed for the special filter requirements when used with fast optics
- For highest contrast even at strongest light pollution, minimizes star size, emphasizes finest nebula detail – indispensable under Bortle 9/8/7/(6) skies
- 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 black frontside outer rim
- Optimized for modern CMOS cameras, but excellent for CCD camera technologies
This new generation of Baader CMOS-filters features:
- Increased contrast
- Ever more narrow passbands
- Reflex-Blocker™ coatings, for largest ever freedom from halos, even under most adverse conditions concerning aux-optics
- FWHM on each filter category carefully designed to allow for 1:1:1 exposures, matched for typical CMOS quantum efficiency and s/n ratio
- Identical filter thickness to existing standards, with utmost care for parfocality
- Blackened edges all around, with filter-lead-side-indicator in the form of a black frontside outer rim, to additionally eliminate any reflection due to light falling onto the edge of a filter
- Each filter coated individually, with sealed coating edge (NOT cut out of a larger plate with coatings left exposed, read more)
- Life-Coat™: evermore hard coatings to enable a non-aging coating for life – even in a most adverse environment
Useful Resources
Filter Cell Specifications
D = Filter Cell Diameter = 30.9 mm / 1.21 in
T = Total Filter Height = 7.6 mm / 0.29 in
C = Filter Cell Height (Excluding Male Thread) = 5.9 mm / 0.23 in
M = Male Thread Length = 1.7 mm / 0.06 in
F = USABLE Female Filter Thread Length = 2.5 mm / 0.09 in
S = Glass Substrate Thickness = 2.0 mm / 0.07 in
CA = Clear Aperture = 26.5 mm / 1.04 in
Other Information
- Country of Manufacture: Germany
Baader CMOS-Optimized 4nm S-II f/3 Ultra-Highspeed Filter - 1.25" Mounted