Symbol	Definition
i	pixel row in image
j	pixel column in image
k	filter number from 0 to 7
l	zoom position or focal length
f	focus position
$m{c}_l$	zoom position in motor-counts [mc]
$m{c}_f$	focus position in motor-counts [mc]
$F{L}_l$	zoom focal length [mm]
$F{D}_{lf}$	distance to target for best-focus [m]
t	exposure time in seconds [s]
$t_e$	extra exposure time due to smear and residual charge [s]
DN	12-bit digital-number value
DN0	12-bit digital-number value with t = 0
$D{N}_8$	8-bit digital-number value after companding
D	dark rate due to dark current [DN/s]
N	zero-mean noise of the pixel [DN]
T	temperature of the focal-plane assembly [∘ C]
$T_{\mathit{amb}}$	temperature at ambient calibration [∘ C]
$A_0$	light collection area of camera [${\mathrm{m}}^2$]
Ω	pixel solid-angle at the center of the array [sr]
g	gain as electrons per digital-number [$\frac{e^{-}}{DN}$]
λ	wavelength of incident light [nm]
$F_{\mathit{ijkl}}$	flat field to correct for vignetting [unitless]
$r_{\mathit{ijk}}(\lambda )$	bandpass efficiency [$e^{-}/ph$]
${\overline{r}}_{\mathit{ijk}}(\lambda )$	integral normalized bandpass efficiency [unitless]
$r_{0,\mathit{ijk}}$	radiometric coefficient [$e^{-}/ph$,nm]
${\beta }_{\mathit{ijk}}$	radiometric temperature coefficient [1/∘ C]