ISIS Application Documentation

photomet

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Perform photometric corrections on a cube

Overview

Parameters

Example 1

Example 2

Example 3

Example 4

Example 5

Example 6

Description

This program performs photometric correction on image pixels acquired under different illumination and viewing geometries by adjusting the brightness and contrast such that the resulting image appears as if obtained under uniform conditions. The photometric correction is applied to each pixel by computing a photometric model based on local photometric angles and a set of parameters that defines the model. Currently, no default values are assigned for any parameter names in the ISIS version of photomet.

Photometric angles can be computed from the following:

SPICE information stored in the image labels
User-entered values for parameter names
Incidence angle, emission angle, and phase angle backplanes
Photometric angle files generated by the user

This program sets all pixels that have an incidence angle and/or emission angle greater than or equal to 90 degrees to NULL pixel values, regardless of the photometric angles resulting from using a topographic model.

The user must select a photometric model and a normalization model, with the option of adding an atmospheric model. Each of these models has a set of parameters that specifies its operation, which the user must provide. The different models can be mixed and matched to produce variations of the photometric correction.

You may enter the desired parameters by using the program GUI, which is recommended
A PVL file containing the photometric parmeters may be used if you opt to use the "frompvl" parameter
Within the GUI you may select a PVL file, and in addition, select the "frompvl" drop-down menu and photomet will load the values from the PVL file into the appropriate parameter names in the GUI for you. Note, if more than one model type for phtname, atmname, or normname parameters are in the PVL file, then the parameter values for the first model type encountered by the program are loaded. Review the parameter values to make sure the correct options are selected and have correct values before executing the program.
Values also can be entered manually at the command line

Note: If any parameter names are entered into the GUI after specifying "frompvl", the new values entered into the GUI will take precedence over the values entered in the PVL file.

There are three aspects of a photometric correction that should be considered when running the photomet program:

The surface photometric function model type that describes the planetary surface. Any one of the surface photometric functions can be used in combination with any of the normalization type models and optionally an atmospheric photometric model.
The atmospheric photometric function model type used when atmospheric scattering is present. The models that end with "1" use a first order scattering approximation, and those that end with "2" use a second order approximation; the second order has slower processing time because it uses more iterations and a quadratic equation versus fewer iterations and a linear equation used in the first order approximation.
The type of normalization applied to the image to equalize the albedo or the topographic contrasts, or a combination of the two. One of the available modes must be selected.

The intent of topographic normalization is to correct for the variation in incidence, emission, and phase angles within and between images. Topographic normalization involves both a multiplicative correction that adjusts the contrast for a unit slope to reference conditions, and an additive correction to keep the average brightness uniform.

In practice, the albedo may be nonuniform, so a multistep process is used:

Photomet is run in albedo mode, which decreases the brightness variations across the individual image and removes any additive atmospheric contribution.
The output image in step 1 is divided by a low-pass-filtered version of itself, which removes the albedo variations if they have broader spatial scales than the topographic shading as is often the case.
And finally, photomet is run again in topography mode on the output image from step 2, which reverses the albedo normalization of the first pass and then applies the topographic normalization.

In the absence of an atmosphere, the "albedo mode" is very simple: the image is divided by the photometric model evaluated at the actual angles and then multiplied by the model at a reference geometry. If an atmosphere is present, the additive component of the atmospheric scattering is subtracted at the real conditions before a multiplicative step, and added back as calculated for the standard conditions at the end. The "mixed mode" of normalization is used for images that span very large ranges of incidence angles. In the mixed mode, the albedo correction is applied at small incidence angles where albedo variations dominate topographic shading, and the topographic normalization is performed at large incidence angles where the reverse is true. A user-specified parameter "incmat" controls the incidence angle at which a smooth transition from one type of normalization to the other takes place.

The normalization models that use an atmospheric correction are albedoatm, shadeatm, and topoatm. If using the GUI interface photomet will automatically exclude all atmospheric models for normaliztion types that do not require an atmospheric correction.

Question: What happens if the normalization model I chose does not perform an atmospheric correction although I have an atmospheric model defined in my PVL file?
Answer: If you have chosen a normalization model that does not perform atmospheric correction, then the image is normalized without applying the atmospheric correction.

New Developments

A new parameter name "chngpar" was added to photomet to allow the user to enter a string consisting of parameter names and values outside of the PVL files. This string replaces any parameter already defined. This is useful when one or two parameter values change for each image but all the other parameter values remain the same.

The parameter name "ZEROB0STANDARD" was shortened to "ZEROB0ST," but the longer name will still work for backward compatibility. The default is to get the user setting for "ZEROB0ST" from the PVL file. If no PVL file exists and the user does not specify a "FALSE" or "TRUE" option, the program will automatically default to "TRUE" to follow the default setting in previous photomet versions. PLEASE NOTE: This change was actually not added because the ability to support aliases (or deprecated) values has not been fully implemented in ISIS. As a result, you must use the full ZEROB0STANDARD parameter name.

The parameter name "INCMAT" is no longer required when the "ALBEDO" normalization model is selected. The parameter name will still appear in the GUI for backward compatibility, but does not need to be defined by the user in the GUI or on the command line.

A set of photomet PVL templates for Mars and other planetary bodies developed in ISIS2 are now available in $ISISROOT/appdata/templates/photometry/ directory. There are also additional examples of PVL files for different photometric models under "Example PVL files," later in this document.

Note: The NoNormalization model has been removed because it duplicated the functionality of the shade model. Use shade with incref=0 and albedo=1.0 instead.

The program photemplate can be used to set up the PVL file containing the selected options for photomet.

The tables below show the models and their related parameter requirements along with the ISIS2 default values. The ISIS2 default values are only meant to serve as possible initial values to test backward compatibility since there are no default values defined in ISIS.

SURFACE PHOTOMETRIC FUNCTION MODELS

**Available photometric function models and required parameter names**
Name	Required parameter names
Hapkehen	B0, hg1, hg2, hh, theta, wh
Hapkeleg	Theta, wh, bh, ch, hh, b0, zerob0st
Lambert	None
LommelSeeliger	None
LunarLambert	L
LunarLambertEmpirical	Phaselist, llist, phasecurvelist
LunarLambertMcEwen	None
Minnaert	K
MinnaertEmpirical	Phaselist, klist, phasecurvelist

**Photometric model parameter names and settings**
Name	Description	ISIS2 default	Valid range
B0	Hapke opposition surge component	0.0	0 <= value
Bh	Hapke Legendre coefficient for single particle phase function	0.0	-1 <= value <= 1
Ch	Hapke Legendre coefficient for single particle phase function	0.0	-1 <= value <= 1
Hg1	Hapke Henyey Greenstein coefficient for single particle phase function	0.0	0 <= value <= 1
Hg2	Hapke Henyey Greenstein coefficient for single particle phase function	0.0	0 <= value <= 1
Hh	Hapke opposition surge component	0.0	0 <= value
K	Minnaert function exponent	1.0	0 <= value
L	Lunar-Lambert function weight	1.0	No limit
Theta	Hapke macroscopic roughness component	0.0	0 <= value <= 90
Wh	Hapke single scattering albedo component	0.5	0 < value <= 1
Zerob0st	Flag to set opposition surge B0 to zero	True	True or False
Phaselist	Phase list for empirical functions	None	String
Llist	Exponent list of limb darkening values	None	String
Klist	Exponent list of limb darkening values	None	String
Phasecurvelist	Phase curve list of brightness values	None	String

The functions are defined as follows, where phase is the phase angle, and u0 and u are the cosines of the incidence and emission angles, respectively:

Lambert: FUNC=u0
LommelSeeliger: FUNC=u0/(u0+u)
Minnaert: FUNC=u0**K * u**(K-1)
LunarLambert (Lunar-Lambert, "lunar" part is Lommel-Seeliger): FUNC=(1-L)*u0 + 2*L*u0/(u0+u)
MinnaertEmpirical: FUNC=B(phase) * u0**K(phase) * u**(K(phase)-1)
LunarLambertEmpirical: FUNC=B(phase) * ((1-L)*u0 + 2*L*u0/(u0+u))

ATMOSPHERIC PHOTOMETRIC FUNCTION MODELS

**Available atmosphereic functions and required parameter names**
Function model name	Required parameters
Anisotropic1	Bha, hnorm, nulneg, tau, tauref, wha
Anisotropic2	Bha, hnorm, nulneg, tau, tauref, wha
HapkeAtm1	Hga, hnorm, nulneg, tau, tauref, wha
HapkeAtm2	Hga, hnorm, nulneg, tau, tauref, wha
Isotropic1	Hnorm, nulneg, tau, tauref, wha
Isotropic2	Hnorm, nulneg, tau, tauref, wha

**Atmospheric models parameter names and settings**
Name	Description	ISIS2 Default	Valid Range
Bha	Coefficient of the single particle Legendre phase function	0.85	-1 <= value <= 1
Hga	Coefficient of single particle Henyey Greenstein phase function	0.68	-1 < value < 1
Hnorm	Atmospheric shell thickness normalized to the planet radius	0.003	0 <= value
Nulneg	Specifies if negative values after removal of atmospheric effects will be set to NULL	NO	YES or NO
Tau	Normal optical depth of the atmosphere	0.28	0 <= value
Tauref	Reference value of tau to which the image will be normalized	0.0	0 <= value
Wha	Single scattering albedo of atmospheric particles	0.95	0 < value < 1

PHOTOMETRIC NORMALIZATION MODELS

**Available photometric normalization functions and required parameter names**
Function name	Normalization function type	Required parameter names
Albedo	Albedo contrasts uniform	Albedo, incref, thresh
AlbedoAtm	Albedo with atmosphere	Incref
Mixed	Albedo at low incidence blended to topo at high incidence	Albedo, incmat, incref, thresh
MoonAlbedo	Special Lunar model	Bsh1, d, e, f, g2, h, wl, xb1, xb2, xmul
Shade	Shaded relief model	Albedo, incref
ShadeAtm	Shaded relief with atmosphere	Albedo, incref
Topo	Topographic shading uniform	Albedo, incref, thresh
TopoAtm	Topographic shading with atmosphere	Albedo, incref

**Normalization model parameter names and settings**
Name	Description	ISIS2 default	Valid range
Albedo	Albedo to which the image will be normalized	1.0	No limit
Bsh1	Albedo dependent phase function normalization parameter	0.08	0 <= value
D	Albedo dependent phase function normalization parameter	0.14	No limit
E	Albedo dependent phase function normalization parameter	-0.4179	No limit
F	Albedo dependent phase function normalization parameter	0.55	No limit
G2	Albedo dependent phase function normalization parameter	0.02	No limit
H	Albedo dependent phase function normalization parameter	0.048	No limit
Incmat	Specifies incidence angle where albedo normalization transitions to incidence normalization	0.0	0 <= value < 90
Incref	Reference incidence angle to which the image will be normalized	0.0	0 <= value < 90
Thresh	Sets upper limit on amount of amplification in regions of small incidence angle	30.0	No limit
Wl	Wavelength in micrometers of the image being normalized	1.0	No limit
Xb1	Albedo dependent phase function normalization parameter	-0.0817	No limit
Xb2	Albedo dependent phase function normalization parameter	0.0081	No limit
Xmul	Used to convert radiance to reflectance or apply a calibration fudge factor	1.0	No limit

Example PVL files:

    Example 1:

    Object = PhotometricModel
      Group = Algorithm
        PhtName = Lambert
      EndGroup
    EndObject
    Object = NormalizationModel
      Group = Algorithm
        NormName = Shade
	Incref = 0.0
	Albedo = 1.0
      EndGroup
    EndObject

    --------------------------------
    Example 2:

    Object = PhotometricModel
      Group = Algorithm
        PhtName = Minnaert
	K = 0.5
      EndGroup
    EndObject
    Object = NormalizationModel
      Group = Algorithm
        NormName = Albedo
	Incref = 0.0
	Incmat = 0.0
	Albedo = 1.0
	Thresh = 30.0
      EndGroup
    EndObject

    --------------------------------
    Example 3:

    Object = PhotometricModel
      Group  = Algorithm
        PhtName = Hapkehen
	Wh = 0.52
	Hh = 0.0
	B0 = 0.0
	Theta = 30.0
	Hg1 = 0.213
	Hg2 = 1.0
      EndGroup
    EndObject
    Object = AtmosphericModel
      Group = Algorithm
        AtmName = hapkeatm2
	Hnorm = 0.003
	Tau = 0.28
	Tauref = 0.0
	Wha = 0.95
	Hga = 0.68
      EndGroup
    EndObject
    Object = NormalizationModel
      Group = Algorithm
        NormName = albedoatm
	Incref = 0.0
      EndGroup
    EndObject

    --------------------------------
    Example 4 (Used to process Clementine UVVIS filter "a" data):

    Object = PhotometricModel
      Group  = Algorithm
        PhtName = LunarLambertMcEwen
      EndGroup
    EndObject
    Object = NormalizationModel
      Group = Algorithm
        NormName = MoonAlbedo
	D = 0.0
	E = -0.222
	F = 0.5
	G2 = 0.39
	H = 0.062
	Bsh1 = 2.31
        Wl = 1.0
        Xb1 = 1.0
        Xb2 = 1.0
      EndGroup
    EndObject

    --------------------------------
    Example 5 (Used to process Clementine UVVIS filter "b" data):

    Object = PhotometricModel
      Group  = Algorithm
        PhtName = LunarLambertMcEwen
      EndGroup
    EndObject
    Object = NormalizationModel
      Group = Algorithm
        NormName = MoonAlbedo
	D = 0.0
	E = -0.218
	F = 0.5
	G2 = 0.4
	H = 0.054
	Bsh1 = 1.6
        Wl = 1.0
        Xb1 = 1.0
        Xb2 = 1.0
      EndGroup
    EndObject

    --------------------------------
    Example 6 (Used to process Clementine UVVIS filter "cde" data):

    Object = PhotometricModel
      Group  = Algorithm
        PhtName = LunarLambertMcEwen
      EndGroup
    EndObject
    Object = NormalizationModel
      Group = Algorithm
        NormName = MoonAlbedo
	D = 0.0
	E = -0.226
	F = 0.5
	G2 = 0.36
	H = 0.052
	Bsh1 = 1.35
        Wl = 1.0
        Xb1 = 1.0
        Xb2 = 1.0
      EndGroup
    EndObject

    --------------------------------
    Example 7 (Used for Mars red filter data to apply empirical photometric models):

    Object = PhotometricModel
    # For Mars red filter images
    # The phase angles at which the coefficient values for the Lunar Lambert
    # Empirical (LunarLambertEmpirical) L and the Minnaert Empirical K approximation are
    # calculated, along with the brightness (phase curve) values at those
    # points (ALL ON ONE LINE!)

      Group = Algorithm
	PhtName = LunarLambertEmpirical
	PhaseList = "0.,10.,20.,30.,40.,50.,60.,70.,80.,90.,100.,110.,120.,130.,140.,150.,160.,170.,180."
	LList = "0.946,0.748,0.616,0.522,0.435,0.350,0.266,0.187,0.118,0.062,0.018,-0.012,-0.027,
	   -0.035,-0.036,-0.037,-0.031,-0.012,-0.010"
	PhaseCurveList = "0.1578,0.1593,0.1558,0.1484,0.1391,0.1292,0.1194,0.1099,0.1008,0.09176,
	   0.08242,0.07234,0.06165,0.05106,0.04091,0.03137,0.02171,0.01038,0."
      EndGroup

      Group = Algorithm
	PhtName = MinnaertEmpirical
	PhaseList = "0.,10.,20.,30.,40.,50.,60.,70.,80.,90.,100.,110.,120.,130.,140.,150.,160.,170.,180."
	KList = "0.518,0.595,0.660,0.709,0.753,0.796,0.837,0.875,0.904,0.922,0.926,0.935,0.954,0.986,
	   1.019,1.063,1.099,1.095,1.090"
	PhaseCurveList = "0.1574,0.1582,0.1546,0.1470,0.1375,0.1273,0.1174,0.1077,0.09797,0.08750,
	   0.07594,0.06466,0.05471,0.04665,0.03935,0.03339,0.02642,0.01482,0."
      EndGroup
    EndObject


  References:

  Chandrasekhar, S., 1960.  Radiative Transfer. Dover, 393 pp.
  Hapke, B. W., 1981. Bidirectional reflectance spectroscopy 1: Theory. J.
     Geophys. Res., pp. 86,3039-3054.
  Hapke, B., 1984. Bidirectional reflectance spectroscopy3: Corrections for
     macroscopic roughness. Icarus, 59, pp. 41-59.
  Hapke, B., 1986. Bidirectional reflectance spectroscopy 4: The extinction
     coefficient and the opposition effect. Icarus, 67, pp. 264-280.
  Johnson, J. R., et al., 1999, Preliminary Results on Photometric Properties of
     Materials at the Sagan Memorial Station, Mars, J. Geophys. Res., 104, 8809.
  Kirk, R. L., Thompson, K. T., Becker, T. L., and Lee, E. M., 2000.
     Photometric modelling for planetary cartography. Lunar Planet. Sci., XXXI,
     Abstract #2025, Lunar and Planetary Institute, Houston (CD-ROM).
  Kirk, R. L., Thompson, K. T., and Lee, E. M., 2001. Photometry of the martian
     atmosphere:  An improved practical model for cartography and photoclinometry.
     Lunar Planet. Sci., XXXII, Abstract #1874, Lunar and Planetary Institute,
     Houston (CD-ROM).
  McEwen, A. S., 1991. Photometric functions for photoclinometry and other
     applications.  Icarus, 92, pp. 298-311.
  Thorpe, T. E., 1973, Mariner 9 Photometric Observations of Mars from November
     1971 through March 1972, Icarus, 20, 482.
  Tomasko, M. G., et al., 1999, Properties of Dust in the Martian Atmosphere from
     the Imager on Mars Pathfinder, J. Geophys. Res., 104, 8987.

Related Applications to Previous Versions of ISIS

This program replaces the following application existing in previous versions of ISIS:

photomet

History

Tammy Becker	1989-02-15	Original version - based on Tammy Becker's photom/photompr programs which were later converted to Randy Kirk's photomet
Janet Barrett	2008-03-07	Added code to acquire the BandBin Center keyword from the input image. This value is needed in case the user chooses the MoonAlbedo normalization method.
Steven Lambright	2008-05-13	Removed references to CubeInfo
Jeannie Walldren	2009-01-08	Added MAXEMISSION and MAXINCIDENCE parameters. Modified code to set off-target pixels to NULL. Added appTests for new parameters. Added user documentation examples.
Eric Hyer	2010-11-10	Added USEDEM parameter.
Janet Barrett	2010-11-22	Added error check for situations where there is not an intersection with the DEM and the local photometric angles are requested.
Janet Barrett	2010-11-23	Added capability to use both ellipsoid and DEM photometric angles in atmospheric corrections. This provides the ability to do shading using a DEM surface.
Janet Barrett	2011-02-22	The USEDEM parameter has been removed and the ANGLESOURCE parameter has been added. The ANGLESOURCE parameter lets you specify the source where the photometric angles will come from: ellipsoid, DEM, or center of image.
Janet Barrett	2011-03-29	The CENTER option of the ANGLESOURCE parameter has been removed and the CENTER_FROM_IMAGE, CENTER_FROM_LABEL and CENTER_FROM_USER options have been added. This allows the user to determine where the center photometric angles will come from.
Janet Barrett	2011-09-23	The following changes were made to the program for the ISIS3.3.0 release: 1) The PHOPAR parameter name was changed to FROMPVL - this was done to have consistent parameter names throughout the photometry software. 2) All radio button options are now accessed through drop down menus. The only radio button options that existed prior to this release were those for choosing the ANGLESOURCE. In order to use any of the drop down menus, click on the drop down menu and hold the mouse button down while navigating to the choice that you want. 3) Added a USEDEM option which will let you determine how the trim is performed. If you don't check the USEDEM box, then trimming is performed based on the photometric angles of the ellipsoid. If you check the USEDEM box, then the trimming is performed based on the photometric angles of the DEM (if one is specified in the image labels). If there is no DEM associated with your FROM file, then the default is to use the ellipsoid. 4) The program now lets you specify the photometric model, atmospheric model, and normalization model through the PHTNAME, ATMNAME, and NORMNAME drop down menus. Prior to this release, you were forced to provide an input PVL file with all of the model information in it. You can now provide the model information through the PVL, the GUI, or a combination of both. If you provide a FROMPVL file, then you need to use the GUI to specify which model(s) to use from that file. If you change any of the model-specific parameters in the GUI, then they will override the values in the FROMPVL file. 5) The BHAREF, HGAREF, and WHAREF parameters have been removed because they were obsolete. 6) The NONORMALIZATION model was removed because it duplicated the functionality of the SHADE model. 7) More photometric models have been added. The Hapke Legendre, Minnaert Empirical, and Lunar Lambert Empirical models have been added. The Minnaert Empirical model has parameters PHASELIST, PHASECURVELIST, and KLIST associated with it. The information for the new parameters is a list of comma delimited values (phase angle goes in PHASELIST, brightness values go in PHASECURVELIST, and limb darkening values go in KLIST). The Lunar Lambert Empirical model has parameters PHASELIST, PHASECURVELIST, and LLIST where LLIST is similar to the KLIST parameter for Minnaert Empirical. 8) A USEDEM parameter has been added which allows the user to determine which photometric angles to use for trimming. If the USEDEM parameter is set to false, then the photometric angles of the ellipsoid are used. If USEDEM is set to true, then the photometric angles of the DEM shape model are used for trimming. 9) Helper buttons were added to the FROMPVL to allow you to View a PVL or to Load a PVL. PLEASE NOTE: When loading a Minnaert Empirical or Lunar Lambert Empirical model from a PVL, only the first value will be loaded into the GUI. This is a known problem and will be fixed in the next patch or release to ISIS. 10) *NOTE* The Minnaert Empirical and Lunar Lambert Empirical models do not load properly from a PVL file when using the Load PVL helper button. This is a known problem and will be fixed in the next patch or release of ISIS.
Janet Barrett	2011-11-04	The ZEROB0STANDARD parameter for the Hapke models was not added to the new update of photomet during the last release. This parameter is responsible for determining if the Hapke opposition surge component B0 is set to zero when calculations are based on standard conditions. This parameter has been added to the new interface to photomet.
Janet Barrett	2012-01-10	The program was fixed to make it backwards compatible with older PVL files. If you tried running this program with an older PVL, then you most likely got the following error message "A Normalization model must be specified before running this program." This message would have occurred even if you had a Normalization model specified in your FROMPVL file. This problem has been fixed. If your FROMPVL file specifies a Normalization model, then you aren't required to specify one through the program interface as well.
Janet Barrett	2012-05-04	A new BACKPLANE option was added to ANGLESOURCE. This BACKPLANE option allows you to input photometric angle information using separate ISIS cube files. Files containing geometric, photometric, etc. information pixel by pixel for the input image file are normally referred to as backplanes. This option was added to support image data that does not have a camera model associated with it. If you have a way to generate the photometric angles for such data, then you will be able to do photometric correction on it. This option is also very useful for speeding up the processing done by photomet. If you have all the photometric information pre-computed, then this information no longer needs to be generated every time the program is run. You can input photometric information using a combination of files and photometric angle constants. For example, if you have a file containing the phase angle for every pixel, a file containing the incidence angle for every pixel, and you know that the emission angle is 0.0 for every pixel, then you can use the PHASE_ANGLE_FILE, INCIDENCE_ANGLE_FILE, and EMISSION_ANGLE fields to input the 2 file names and the emission angle constant.
Ella Mae Lee	2012-10-05	Improved the documentation, reference Mantis issue #453, #843
Janet Barrett	2012-10-24	The following changes were made to the program: 1) Added a new parameter, CHNGPAR, which allows the user to change any of the model- related parameter settings without having to specify the model name on the command line or in the GUI. Before the CHNGPAR parameter was added, you could only change a model-related parameter on the command line or in the GUI if you also specified the model name using the PHTNAME, ATMNAME, or NORMNAME parameter. Any value you set using the CHNGPAR parameter will override changes that are specified in the GUI. Any value that is changed through the GUI will override values specified in the FROMPVL file. PLEASE NOTE: Any parameter that you type into the CHNGPAR string MUST be spelled correctly and using the full name (no partial parameter names). Otherwise, the program will not recognize the parameter and it won't get used. 2) Added new output groups to the print.prt log file so that the user can see exactly which values were used to run photomet. The new groups that get written to the print.prt file include NormalizationModelParametersUsed, AtmosphericModelParametersUsed, and PhotometricModelParametersUsed. 3) Fixed photomet so that the INCMAT parameter is no longer required for the ALBEDO normalization model. The INCMAT parameter is not used by the ALBEDO normalization model, so the user is no longer required to input an INCMAT value for that model. 4) Fixed a problem which was causing the NULNEG and ZEROB0STANDARD parameters to be loaded incorrectly if specified in the FROMPVL file. 5) Added a more meaningful error message when a normalization model is not specified by the user either through the GUI, command line, or FROMPVL file. 6) Changed the ZEROB0STANDARD parameter name to ZEROB0ST. This was to help prevent the user from needing to resize the GUI each time they opened it because the parameter name was too long. We are maintaining backwards compatibility by supporting both ZEROB0STANDARD and ZEROB0ST in the photomet code. This will allow you to run a script with the old parameter name without any problems.
Janet Barrett	2012-12-07	PLEASE NOTE (in reference to change made on 2012-10-24): The backwards compatibility for the shorter ZEROB0ST parameter name has not been fully implemented in ISIS. As a result, this change has been removed and the full ZEROB0STANDARD parameter name must be used. Support for aliases (deprecated values) must be fully implemented in ISIS before the shorter parameter name (ZEROB0ST) will be available. Fixes #1288.
Lynn Weller	2013-02-25	Removed links to applications imbedded in text and replaced with italicized application name. Added application links to the "Related Objects and Documents" section of the documentation. Fixes mantis ticket #1525.
Kelvin Rodriguez	2016-08-24	Added cast to void on 'changePar.simplified()' function call to silience unused return value warnings on OS X
Curtis Rose	2016-11-16	Decoupled ANGLESOURCE and USEDEM parameters. They were working incorrectly before and were tangled together a bit. They are separated now and working as expected. Anglesource DEM makes the photometric calculations based on the DEM of the image if it exists. Anglesource ELLIPSOID makes the photometric calculations based on the radius obtained from the DEM shape model. Usedem true trims the image using the photometric calculations on the radius obtained from the DEM shape model. Usedem false trims the image using the from the IAU/NAIF target body file, which is defined within the cube's kernel group as the TargetAttitudeShape. Fixes #4180.
Lauren Adoram-Kershner	2019-11-07	Added a warning when the 'DEM' angle source option is used with 'mixed' or 'topo' normalization method. Fixes #3451 and #3452.

Parameter Groups

Files

Name	Description
FROM	Input cube file
TO	Output cube file
FROMPVL	Input PVL file

Change Parameters

Name	Description
CHNGPAR	Change parameter string

Trim Parameters

Name	Description
MAXEMISSION	Maximum emisson angle to trim image
MAXINCIDENCE	Maximum incidence angle to trim image
USEDEM	Specify if DEM photometric angels will be used to trim image

Angle Source Options

Name	Description
ANGLESOURCE	Source of photometric angles: ELLIPSOID, DEM, CENTER, or FILE
PHASE_ANGLE_FILE	Phase angle cube file
INCIDENCE_ANGLE_FILE	Incidence angle cube file
EMISSION_ANGLE_FILE	Emission angle cube file
PHASE_ANGLE	Center phase angle
INCIDENCE_ANGLE	Center incidence angle
EMISSION_ANGLE	Center emission angle

Photometric Model

Name	Description
PHTNAME	Photometric model to be used
THETA	Macroscopic roughness angle
WH	Single scattering albedo
HG1	Hapke Henyey Greenstein coefficient
HG2	Hapke Henyey Greenstein Coefficient
BH	Hapke Legendre coefficient
CH	Hapke Legendre coefficient
HH	Hapke opposition surge
B0	Hapke opposition surge
ZEROB0STANDARD	Specifies if opposition surge is set to zero under standard conditions
L	Lunar-Lambert function weight
K	Minnaert function exponent
PHASELIST	Empirical functions phase angle list
KLIST	Minnaert Empirical function limb darkening parameter list
LLIST	Lunar Lambert Empirical function limb darkening parameter list
PHASECURVELIST	Empirical functions phase curve (brightness) value list

Atmospheric Model

Name	Description
ATMNAME	Atmospheric model to be used
NULNEG	Specifies if negative values will be set to NULL
TAU	Optical depth of atmosphere
TAUREF	Reference value of tau
HGA	Henyey Greenstein coefficient
WHA	Single scattering albedo
BHA	Legendre coefficient
HNORM	Atmospheric shell thickness

Normalization Model

Name	Description
NORMNAME	Normalization model to be used
INCREF	Reference incidence angle
INCMAT	Photometric transition incidence angle
THRESH	Amplification threshold
ALBEDO	Albedo
D	Albedo normalization parameter
E	Albedo normalization parameter
F	Albedo normalization parameter
G2	Albedo Normalization Parameter
H	Albedo normalization parameter
XMUL	Radiance to reflectance or calibration factor
WL	Wavelength
BSH1	Albedo normalization parameter
XB1	Albedo normalization parameter
XB2	Albedo normalization parameter

Files: FROM

Description

This is the input filename that will be photometrically corrected.

Type	cube
File Mode	input
Filter	*.cub

Type	filename
File Mode	input
Default Path	$ISISROOT/appdata/templates/photometry
Internal Default	None Specified
Filter	*.pvl

Type	double
Default	90.0
Minimum	0.0 (inclusive)
Maximum	90.0 (inclusive)

Band	Wh	B0	Hh	Hg1	Hg2
Red	0.52	0.025	0.17	0.213	1.0
Green	0.29	0.29	0.17	0.19	1.0
Blue	0.16	0.995	0.17	0.145	1.0

Type	boolean
Default	FALSE

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Documentation Versions

photomet

Description

SURFACE PHOTOMETRIC FUNCTION MODELS

ATMOSPHERIC PHOTOMETRIC FUNCTION MODELS

PHOTOMETRIC NORMALIZATION MODELS

Categories

Related Applications to Previous Versions of ISIS

Related Objects and Documents

Applications

History

Parameter Groups

Files

Change Parameters

Trim Parameters

Angle Source Options

Photometric Model

Atmospheric Model

Normalization Model

Files: FROM

Description

Files: TO

Description

Files: FROMPVL

Description

Change Parameters: CHNGPAR

Description

Trim Parameters: MAXEMISSION

Description

Trim Parameters: MAXINCIDENCE

Description

Trim Parameters: USEDEM

Description

Angle Source Options: ANGLESOURCE

Description

Exclusions

Exclusions

Exclusions

Exclusions

Exclusions

Inclusions

Exclusions

Angle Source Options: PHASE_ANGLE_FILE

Description

Angle Source Options: INCIDENCE_ANGLE_FILE

Description

Angle Source Options: EMISSION_ANGLE_FILE

Description

Angle Source Options: PHASE_ANGLE

Description

Angle Source Options: INCIDENCE_ANGLE

Description

Angle Source Options: EMISSION_ANGLE

Description

Photometric Model: PHTNAME

Description

Exclusions

Exclusions

Exclusions

Inclusions

Exclusions

Inclusions

Exclusions

Exclusions

Inclusions

Exclusions

Exclusions

Inclusions

Exclusions

Inclusions

Exclusions

Inclusions

Photometric Model: THETA

Description

Photometric Model: WH

Description

Photometric Model: HG1

Description

Photometric Model: HG2