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O-III 6.5nm 2" narrowband filter, Explore Scientific
Summary description:
Explore Scientific O-III 6.5nm 2" narrowband filter isolates the doubly ionized oxygen emission lines for enhanced contrast in planetary nebulae and certain emission nebulae. Designed as a 2-inch (50.8 mm) eyepiece/diagonal-mounted filter with 6.5 nm bandwidth, it reduces broadband skyglow and increases visibility of O-III rich details for visual observing and imaging.