Filter—XNite BPG 830nm Infrared Bandpass
Graphs are in nanometers. Visible light is approximately 390 - 650 nm (the human eye can see very weakly into the 700-800nm range). Graphs used by permission of Coastal Optical System.
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This maxmax.com filter uses coatings to achieve its bandpass filtration and might have undesirable off-center effects with wide-angle lenses.