STRING--REQUIRED INP=(D1,D2,D3,...,Dn) Inputs are flat-field images in order of increasing exposure. If multiple frames are acquired at a given exposure, these frames may be combined via PICSUM.
STRING--REQUIRED OUT=(CAL,SAT,ERR,RMS,DC) The output files (CAL,SAT,ERR,RMS,DC) are images in the same format as the input flat-field frames (400x400 or 800x800 for Galileo, 256x256, 512x512, or 1024x1024 for Cassini):). If the keyword LINEAR is specified (the default), all five outputs are required. If SLOPE is specified, then DC should not be specified, and SAT, ERR, and RMS are optional. CAL is the Radiometric File, and contains the inverse slope term of the light-transfer function for each pixel position (i,j). The elements of CAL are REAL*4 values z(i,j) such that: z(i,j) = SCALE/c for normal pixels (inverse slope term) = 0.0 for an unsuccessful fit. SAT contains the saturation DN value (DNfw) for each low-full-well pixel. The elements of SAT are 16-bit integers s(i,j) such that: s(i,j) = 32767 for normal pixels = DNfw for low-full-well pixels = -1 for an unsuccessful fit. ERR contains the maximum absolute deviation (Emax) of the input pixels from the fitted light-transfer curve. The elements of ERR are 16-bit integers f(i,j) such that: f(i,j) = -1 for an unsuccessful fit = Emax*FSCALE otherwise. where FSCALE is specified by the FITSCALE parameter (default=1.0). RMS contains the RMS error (Erms) resulting from the fit. The elements of RMS are 16-bit integers r(i,j) such that: r(i,j) = -1 for an unsuccessful fit = Erms*FSCALE otherwise. where FSCALE is specified by the FITSCALE parameter (default=1.0). If the keyword LINEAR is specified, the output Dark-Current File (DC) contains the offset terms (Do) resulting from the fit. The elements of DC are 16-bit integers d(i,j) such that: d(i,j) = 0 for an unsuccessful fit = 128*Do otherwise.
STRING--OPTIONAL Specifies the input Dark-current file. This parameter is required when the parameter FIT is equal to SLOPE.
STRING--OPTIONAL Specifies the input extended Dark-current file. This paremter is required when extened exposure flat fields are used in conjuntion with normal exposure flat fields as input. NOTE: The parameters DC & EXTEXP must also be specified.
INTEGER--REQUIRED for Galileo Specifies camera gain state. Valid values are 10, 40, 100, 400 for Galileo, 40, 100, 400, 1400 for Cassini. This parameter must be given for Galileo, but if not given for Cassini is extracted from the VICAR label.
Specifies whether LIGHT is in LUMINANC (Relative-foot-Lamberts ) or RADIANCE (nanowatts/cm**2/sr/nanometer). UNITS should be LUMINANC for Galileo and RADIANCE for Cassini).
REAL-REQUIRED for Galileo LIGHT gives the light cannon setting (in foot-lamberts or nanowatts/cm**2/sr/ nanometer) at which the flat field images were exposed (assumed to be constant throughout the sequence). This parameter must be given for Galileo, but if not given for Cassini is extracted from the VICAR label.
REAL--OPTIONAL Specifies the commanded exposure times (in milliseconds) for each input frame in the light-transfer sequence. The exposures must be input either via the EXPOSURE or SHUTTER parameter (see below). Not needed for the DC or EDC input frames. EXPOSURE or SHUTTER must be given for Galileo, but if not given for Cassini is extracted from the VICAR label.
INTEGER--OPTIONAL
This parameter is for Galileo only. Gives the shutter setting for each flat
field input image. The shutter setting is related to commanded exposure time
as follows:
Shutter Exposure | Shutter Exposure
Setting time (ms) | Setting time (ms)
-------------------------------|---------------------------------
0 0 | 16 800
1 4 1/6 | 17 1066 2/3
2 6 1/4 | 18 1600
3 8 1/3 | 19 2133 1/3
4 12 1/2 | 20 3200
5 16 2/3 | 21 4266 2/3
6 25 | 22 6400
7 33 1/3 | 23 8533 1/3
8 50 | 24 12800
9 66 2/3 | 25 17066 2/3
10 100 | 26 25600
11 133 1/3 | 27 34133 1/3
12 200 | 28 51200
13 266 2/3 | 29 0
14 400 | 30 0
15 533 1/3 | 31 0
INTEGER--OPTIONAL
Specifies the picture scale for each input frame.
E.g. NUMB=([Ndc,]N1,N2,N3,...,Nn[,Nedc])
If an input frame Di represents multiple frames that have been combined via
PICSUM, then Ni should equal the number of frames added together (=1 for
single frames). When either a dark-current (DC) or an extended-dark-current
frame (EDC) are specified, then the picture scales: "Ndc" and "Nedc" should
be included, as needed. If NUMB is defaulted, the picture scale is retrieved
from the image labels.
INTEGER--OPTIONAL - GALILEO only
EXTEXPO specifies the exposure at which the extended-dark-current
correction is to be applied.
galgen (D1,D2,D3,D4,D5,D6,D7) CAL DC=DC EDC=EDC EXTEXPO=5
The correction will be applied here to frames D5, D6, and D7.
NOTE: The parameters DC & EDC must also be specified.
REAL--OPTIONAL--Default=1.0 SCALE specifies scaling of the output slope terms. Instead of outputing 1/c in the slope file, SCALE/C is output.
KEYWORD--OPTIONAL--Default=LINEAR FIT specifies whether, while fitting the input data points to the light- transfer curve, to solve for the slope term only (FIT=SLOPE) or to solve for both the slope and offset terms (FIT=LINEAR). If FIT=LINEAR is specified, the input data points D1,D2,D3,...,Dn are fitted to the curve: Di = C*Ei + DC where the exposures Ei are computed from the commanded exposure times, light-cannon setting, and shutter-offsets (see EXPOSURE, SHUTTER, LUMINANC, and OFFSET parameters). The inverses of the resulting slopes (1/C) are output to the Radiometric File (CAL). The resulting offsets are output to the output dark-current file (DC). Even though the input DC frame is not used in any calculations, it still must be included as the last input frame. If FIT=SLOPE is specified, the input data points D1,D2,D3,...,Dn are fitted to the curve: Di = C*Ei + DC and DC is the input dark-current extracted from the DC parameter. The inverses of the resulting slopes (1/C) are output to the Radiometric File (CAL).
REAL--OPTIONAL--Default=1.0 Specifies a number (FSCALE) used to scale the maximum residual error (ERR) and rms error (RMS) resulting from the least squares fit. See OUT parameter for details.
KEYWORD--OPTIONAL The keyword LFWPT enables the low-full-well-pixel test for automatically scanning for low-full-well pixels by checking for non-linearities in the input data points. Starting with the first n data points (where n is specified via the SKIP parameter), the points are iteratively included in the fit. The next point (not yet included) is checked to see if it falls more than a certain distance (determined from the ERROR parameter) below the fitted curve (in units of DN). If a point is rejected, then all points above this level are also thrown out, and the raw dn of the last pixel used in the fit is placed into the SAT file as a record of the saturated DN level (low-full-well for the CCD). If the keyword LFWPT is not specified, then the test is suppressed, and the positions of the low-full-well pixels are retrieved from tables built into the program.
INTEGER--OPTIONAL--Default=4 Specifies number of exposures at low end to skip before applying the low full well pixel test. See LFWPT for details.
REAL--OPTIONAL-Default=(.05,1.)
ERROR=(delta1,delta2)
The ERROR parameter specifies the error threshold EPS (in DN) as a linear
function of the exposure e (in relative-foot-Lambert-msec or picoamp-msec):
EPS = delta1*e + delta2
The error threshold is applied in the low-full-well-pixel test (see
parameter LFWPT).
STRING--REQUIRED Specifies the Shutter-Offset File. The file is generated by program CCDRECIP.
STRING--OPTIONAL Specifies the name of the SRCH-format text file containing the names of the input files to be processed. This is an alternative to listing the filenames on the command line with the INP parameter. Inputs are flat-field images in order of increasing exposure. If multiple frames are acquired at a given exposure, these frames may be combined via PICSUM.