Non-linearity Correction

Detector non-linearity corrections are applied to Classic Cam, IRCAM, and INGRID. For IRCAM the correction is $3.3\times10^{-6}$ times the square of the bias-subtracted signal. For INGRID the measured-to-actual counts is given by the expression $1.0 - 1.2247 \times 10^{-6} * M - 7.68045 \times 10^{-11} * M^2$, where M is the measured ADU count, although it is actually applied after the pre-exposure readout is subtracted from the post-exposure integration. For Classic Cam the correction is 1.625$\times10^{-6}$ $*$ (1 $+$ overhead$/$exposure_time), where the overhead is 2 $*$ speed $*$ number of pre-exposure reads $+$ (speed $+$ readout time ) $*$ number of post-exposure reads. The various parameters in this expression are either read from the headers or taken verbatim from an IRAF script cited in the user manual.
[CLASSICCAM/_CORRECT_NONLINEARITY_,
IRCAM/_CORRECT_NONLINEARITY_,
INGRID/_CORRECT_NONLINEARITY_PRE_POST_]