William Herschel discovered infrared light in 1800 (Herschel 1800). R. W. Wood made the first outdoor infrared photograph in 1910 (Wood 1910). Robert Greenler was the first to publish an infrared photograph of a rainbow in 1971 (Greenler 1971). Vollmer and Shaw were the first to publish a pure infrared photograph of a 22° ice crystal halo (Figure 1, Volmer and Shaw 2017). All of these published findings involve near infrared (NIR) light, with wavelengths slightly longer than red light (i.e., not thermal infrared radiation).
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