The SVBONY Narrowband OIII filter is designed for nebula observation allowing 5nm bandwidth of light centered on a wavelength of 500.7nm 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. Please Note: This OIII filter is NOT for use on the Sun.
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