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O‑III Filter 12nm 1.25" for telescopes, Explore Scientific
Summary description:
Narrowband O‑III filter by Explore Scientific, 12 nm bandwidth in a 1.25" (31.7 mm) format. Designed to transmit doubly ionized oxygen emission lines while blocking unwanted light, it improves contrast on nebulae and emission regions when used with telescopes and compatible eyepieces or cameras. Useful for visual observing and astrophotography under light-polluted or dark skies.