• The Narrowband OIII 5nm 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, high- and low-pressure sodium vapor lights and the natural light caused by neutral oxygen emission;
• The H-Alpha 5nm is an extremely narrow emission-line filter that works by allowing a 5nm bandwidth of light, centered on the 656nm wavelength through, and blocking the transmission of contrast-killing light pollution wavelengths;
• The SII 6.5nm Extra Narrowband Filter transmits a 5nm bandwidth of light that is centered at 672nm and drastically reduces other transmissions, including wavelengths of light that are responsible for light pollution. Due to the narrow bandwidth and high transmission rate of this filter, you will experience a major boost to contrast;
• The Blocks infrared wavelengths from 700nm to 1100nm so you don't need a separate IR-Cut filter, suitable for used for deep sky photographic and all are NOT for use on the Sun; 90% transmission of the filters can block the light from mercury and sodium vapour lamps; Standard M28.5x0.6 thread interface, can de directly into the 1.25 inch barrel of your telescope eyepiece.

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