• Baader H-alpha / O-III / S-II f / 2 Highspeed Filter Set - Precision Grade
• 6.5 nm FWHM, recommended for extremely fast optical systems from f / 3.4 to f / 1.8
• Specially designed for the special filter requirements when used with fast optics like the Starizona HyperStar and Celestron RASA astrographs
• Reflex-Blocker ™ hard coated and planoptically 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

The new generation of Baader CMOS-optimized filters features:

• CMOS-Optimized Baader Filter
• 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