Altair 2" H-Alpha, S-II and O-III DualBand ULTRA 4nm Filter-Set

This innovative combination of filters allows astrophotographers to explore the hidden secrets of the universe with breathtaking clarity and detail. Each of the three filters - H-Alpha, S-II and O-III - is specifically designed to capture certain emissions in the electromagnetic spectrum. The H-alpha filter captures the red emissions of ionised hydrogen, while the S-II filter selectively filters the emissions of ionised sulphur and the O-III filter selectively filters the emissions of ionised oxygen.

What makes this filter system special is its ultra-thin 4nm bandwidth. This minimal bandwidth enables exceptional light transmission and reduces disturbing artefacts to a minimum. The result is images of astonishing clarity and detail that capture the beauty of the universe in unprecedented splendour.

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