Baader CMOS-Optimized 3.5nm H-Alpha Ultra-Narrowband Filter - 31mm Round Unmounted
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- Baader H-alpha Ultra-Narrowband Filter – Premium Grade
- 3.5 nm FWHM (to harmonize the exposure time with O-III / S-II), 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
We explicitly warn against observing the sun with a DeepSky 6.5 nm (equivalent to 65 Ångstroem) H-alpha narrowband filter, specialized solar chromosphere and prominence filters from SolarSpectrum start at 0.8 Ångstroem. Photographic experiments with a camera are theoretically possible, but by no means observe the sun with naked eyes – you endanger your eyesight!
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
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
- Baader H-alpha Ultra-Narrowband Filter – Premium Grade
- 3.5 nm FWHM (to harmonize the exposure time with O-III / S-II), 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
We explicitly warn against observing the sun with a DeepSky 6.5 nm (equivalent to 65 Ångstroem) H-alpha narrowband filter, specialized solar chromosphere and prominence filters from SolarSpectrum start at 0.8 Ångstroem. Photographic experiments with a camera are theoretically possible, but by no means observe the sun with naked eyes – you endanger your eyesight!
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
| Product Banner Type | new |
|---|---|
| Free Shipping Graphic | Free US Shipping |
| Hide Found a better Shipped Price on Frontend? | No |
Baader CMOS-Optimized 3.5nm H-Alpha Ultra-Narrowband Filter - 31mm Round Unmounted # FCHALNU-RD31 2961326