Optolong SII 6.5nm Imaging Narrowband Filter

Optolong SII 6.5nm Imaging Narrowband Filter

Optolongimproved narrowband SII6.5nm 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 highand low pressure sodium vapor lights and the unwanted natural light caused by neutral oxygen emission in our atmosphere (i.e. skyglow).

Main use and performance:

Suitable for viewing on faint emission nebula of H-Alpha line in full moonlight or in severe light pollution.

Hubble look of images can be made by the combination of H-alpha, OIII-CCD and SII-CCD, such as the famous “Pillars of Creation” (M16 Eagle Nebula).

Narrowband imaging with SHO kit (H-alpha7nm, OIII 6.5nm and SII6.5nm) can be done with the moon up in heavy light pollution, so your equipment is not sitting dormant for several weeks.

Narrowband filter do not eliminate the effects of light pollution or increase the object’s brightness. In many cases, they increase the contrast between nebula and night sky, not brightening the nebula.