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G01J—MEASUREMENT OF INTENSITY, VELOCITY, SPECTRAL CONTENT, POLARISATION, PHASE OR PULSE CHARACTERISTICS OF INFRARED, VISIBLE OR ULTRAVIOLET LIGHT; COLORIMETRY; RADIATION PYROMETRY
G01J1/00—Photometry, e.g. photographic exposure meter
G01J1/10—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void
G01J1/12—Photometry, e.g. photographic exposure meter by comparison with reference light or electric value provisionally void using wholly visual means
G01J1/122—Visual exposure meters for determining the exposure time in photographical recording or reproducing
G01J1/124—Visual exposure meters for determining the exposure time in photographical recording or reproducing based on the comparison of the intensity of measured light with a comparison source or comparison illuminated surface
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Spectroscopy & Molecular Physics
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Investigating Or Analysing Biological Materials
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