Baader CMOS-Optimized 4nm S-II Ultra-Narrowband Filter - 1.25" Mounted
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Important Note About Torn Baader Filter Seals:
Recently, Baader started applying a new filter label on many filters that goes over the edge of the case and also acts as a seal. Unfortunately, these labels rip far too easily during transport, giving the false appearance that the filter case has been previously opened. Many filters we now get from Baader arrive like the ones shown in the photos below, and many others will rip en route from us to you. Rest assured that ALL filters we ship to you are brand new and unopened as received from Baader, whether the seal is intact or partially/completely ripped.
 |
 |
Baader has agreed to revert to their old design of 2-piece labels, but until they use up their current labels, we will continue to have this problem for a while and you might also get a mix of different filter label types. Thank you for your understanding.
- Baader S-II Ultra-Narrowband Filter – Premium Grade
- 4 nm FWHM, recommended for optical systems from f/10 to f/3.5
- 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 Ultra-Narrowband Filter – Premium Grade
- 4 nm FWHM, recommended for optical systems from f/10 to f/3.5
- 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
Important Note About Torn Baader Filter Seals:
Recently, Baader started applying a new filter label on many filters that goes over the edge of the case and also acts as a seal. Unfortunately, these labels rip far too easily during transport, giving the false appearance that the filter case has been previously opened. Many filters we now get from Baader arrive like the ones shown in the photos below, and many others will rip en route from us to you. Rest assured that ALL filters we ship to you are brand new and unopened as received from Baader, whether the seal is intact or partially/completely ripped.
|
|
Baader has agreed to revert to their old design of 2-piece labels, but until they use up their current labels, we will continue to have this problem for a while and you might also get a mix of different filter label types. Thank you for your understanding.
- Baader S-II Ultra-Narrowband Filter – Premium Grade
- 4 nm FWHM, recommended for optical systems from f/10 to f/3.5
- 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 Ultra-Narrowband Filter - 1.25" Mounted