The raw data in the visible channels are relativized and normalized at the CDA, but no calibration is applied. The GVAR stream contains the imager data in 10-bit words and the sounder data in 16-bit words. The imager data are currently relativized and normalized, the sounder data relativized only. The GVAR also carries on/off flags for the status of relativization and normalization, as well as the values of X₀ (the constant space output) , the normalization look-up tables, the identity of the reference detector, and an identifier (including the creation date) of the normalization look-up tables. In addition, it contains the visible-channel pre-launch calibration coefficients (three per detector, but with the quadratic coefficients identically zero) and the factor that converts radiance to reflectance factor.

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