Optolong HSO 7nm Filter Kit

Optolong HSO Narrowband Filter Kit

This Filter Kits Includes All SII 6.5nm, OIII 6.5nm and Ha 7nm Filter. Suitable For Narrowband Imaging

Included

OIII 6.5nm Filter

Extra Narrowband OIII-CCD 6.5nm filter is designed for nebula observation allowing 6.5nm bandwidth of light centered on a wavelength of 500nm through, which corresponds to OIII emission lines, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow)

OIII emits 495.9nm and 500.7nm and it is a blue-green colored filter. Many of images of planetary nebula and supernova remnants are taken only with H-alpha and OIII filters. They show great structural details, but have natural colors, looking like an RGB image

SII 6.5nm Filter

Extra narrowband SII-CCD 6.5nm filter (Sulful II for CCD) is designed for nebula observation allowing 6.5nm bandwidth of light centered on a wavelength of 672nm through, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow)

Ha 7nm Filter

H-Alpha 7nm filter is the most popular narrowband filter allowing 7nm bandwidth of light centered on a wavelength of 656nm through, and reducing the transmission of certain wavelengths of light, specifically those produced by artificial light including mercury vapor, and both high and low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow). Best choice of narrowband H-alpha astrophotography filter for highest contrast and revealing subtle nebula details