ISIS Application Documentation
Radiometrically calibrates a Mars Exploration Rover (MER)
Microscopic Imager(MI) image
Description
mical performs radiometric corrections to images acquired by the MER
MI camera. MI images taken during science operations have 1024 samples
and 1024 lines and are single bands. The pre calibration images are signed
word or 16 bit images. Subareas can be aquired but this was rarely done during
the mission.
mical has a number of parameters required to process MER MI image
data. Most of these parameters are read from an ISIS parameter defaults
file located in the mer directory specified in the IsisPreference file.
This file has the form:
$mer/calibration/mical.ker.xxx
where "xxx" is a positive number.
mical will search for the parameter file with the highest number and
load all its defaults needed to process MI images. Note that the
caller may explicity provide an alternative ISIS parameter defaults
file name in the "CALKERNEL" input parameter if they have their own
set of defaults that applies to MI data. See an existing calibration
file for details on how to configure this file.
The level of calibration output can be selected. by choosing one of the
output options, the user can choose to dark current correct, dark current and
flat field, or dark current, flat field and output in I/F values.
The dark current correction equation mical implements is as follows:
r = dn - (rpi + rpv) + (zei * zev) + (aai * aav)
Where:
r is the aver signal being generated at the focal plane
dn is the input pixel value
rpi is the referance pixel dn
rpv is the referance pixel correction value
zei is the zero exposure pixel dn
zev is the zero exposure correction value
aai is the active area pixel dn
aav is the active area correction value
The user can choose to not correct for the reference pixel, zero exposure
or active area by selecting or deselecting the RPCORRECTION, ZECORECTION,
or AACORRECTION checkbox. The program will also determain if these
corrections should be applied. If the ShutteEffectCorrectionFlag is set to "TRUE"
in the image labels, the reference pixel, and zero exposure will not be applied.
If a flat fielded output is chosen:
r = dn / f
where:
r is the corrected output value
dn is the input pixel that has been dark current corrected
f is a flat field pixel
if the "ShutteEffectCorrectionFlag is false and the exposure duration is greater
them zero and less them 1000 and the image is mot equal to 1024 samples, a
image smear correction is applied.
Categories
Applications
History
| Robert Sucharski | 2007-02-16 |
Original version
|
| Christopher Combs | 2017-05-19 |
Changed pvl.DIFF of input for all app tests to ignore file names. Allows test to pass when not
using default data area. Fixes #4738.
|
| Jesse Mapel | 2019-05-15 |
Now loads latest Mars satellites kernel because the planets kernel (de430)
only provides Mars Barycenter.
|
|
Parameter Groups
Files
|
Name
|
Description
|
| FROM |
Level 0 MER MI image
|
| TO |
Level 1 MER MI image
|
| CALKERNEL |
PVL kernel containing calibration prameters
|
| REFPIXIMAGE |
Referance Pixel image (ERP)
|
| FLATFIELD |
The flat field image used in correction
|
Output Options
|
Name
|
Description
|
| CALSTAGE |
The calibration stage to process
|
Entry Option
|
Files:
FROM
Description
An uncalibrated MER MI image.
|
Type
| cube |
|
File Mode
| input |
|
Filter
|
*.cub *.CUB
|
Files:
TO
Description
The resultant radiometrically calibrated cube
|
Type
| cube |
|
File Mode
| output |
|
Pixel Type
| real |
|
Filter
|
*.cub *.CUB
|
Files:
CALKERNEL
Description
If you do not enter a file, mical will search for a file with the form:
$mer/calibration/mical.kernel.xxx
where "xxx" is a positive number.
the kernel with the highest version (xxx) will be used.
See an existing calibration
file for details on how to configure this file.
|
Type
| filename |
|
File Mode
| input |
|
Internal Default
| Internal Default |
Files:
REFPIXIMAGE
Description
At times, a referance pixel image was aquired when image data was
taken. If a referance pixel image was acquired, it can be used in the
calibration. A referance pixel image uses the designation "ERP" rather
then "EFF" in the file name.
|
Type
| cube |
|
File Mode
| input |
|
Internal Default
| Use Model Value |
|
Filter
|
*.cub *.CUB
|
Files:
FLATFIELD
Description
User can enter a flat field image that will be used in the correction.
If no value is entered, then the file listed in the calibration kernel
will be used.
|
Type
| cube |
|
File Mode
| input |
|
Internal Default
| Use value in kernel |
|
Filter
|
*.cub *.CUB
|
Output Options:
CALSTAGE
Description
This parameter allows the user to control what calibration step will
be applied to the input image. if "DARK" is selected, then only a
dark current correction is preformed. If "FLAT" is selected, the
image is corrected for dark current and a flat field correction is
applied. if "IOF" is chosen then the final outut will in refiectance
values.
|
Type
| string |
|
Default
|
IOF
|
|
Option List:
|
|
Option |
Brief |
Description |
| DARK |
Dark Current correction
|
The output file will be a dark current corrected file.
|
| FLAT |
Dark Current and Flat Field correction
|
The output will be a dark current corrected and flat field
corrected. This is the "CFD" image in the PDS archive.
|
| IOF |
Convert Dark current and Flat Field corrected image to I/F values
|
The output file will be a flat field corrected image that has been
converted to refiectance. This is the "IFF" file in the PDS
archive.
|
|
Entry Option:
CCDtemp
Description
A user defined CCD temperature that will be used in calculations that use
the CCD temperature. If entered, this value will be used rather then the
temperature in the image labels.
|
Type
| double |
|
Internal Default
| Temperature from Labels |
Entry Option:
PCBtemp
Description
A user defined PCB temperature that will be used in calculations that use
the PCB temperature. If entered, this value will be used rather then the
temperature in the image labels.
|
Type
| double |
|
Internal Default
| Temperature from labels |
Entry Option:
RPCORRECTION
Description
If this option is selected, the reference pixel correction will be applied.
if the ShutteEffectCorrectionFlag is set to TRUE then the reference pixel
correction is not applied, even if this parameter is set to true. The
default is true which will apply the correction.
|
Type
| boolean |
|
Default
| TRUE |
Entry Option:
ZECORRECTION
Description
If this option is selected, the zero exposure correction will be applied.
if the ShutteEffectCorrectionFlag is set to TRUE then the zero exposure
correction is not applied, even if this parameter is set to true. The
default is true which will apply the correction.
|
Type
| boolean |
|
Default
| TRUE |
Entry Option:
AACORRECTION
Description
If this option is selected, the active area. correction will be applied.
The default is true which will apply the correction.
|
Type
| boolean |
|
Default
| TRUE |