Baader 3.5 / 4nm Ultra-Narrowband Filter-Set CMOS-optimised (H-alpha / O-III / S-II)

• Baader H-alpha / O-III / S-II Ultra-Narrowband Filter Set Premium Grade
• 3.5 / 4 nm FWHM (to harmonize the exposure time from H-alpha 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 3.5 nm (equivalent to 35 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!