MV4920

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MV-4920 Physical Modeling Remote Sensing Basics
Nomenclature Atmospherics Illumination Surface
physics EO/IR
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Illumination Problem
Find the Incident spectral radiance Li(xs,ys,?i,?
i,?) from all directions.
Radiance -L- radiance means watts flowing into a
unit area ( As ) from a solid angle ?i watts/
cms2 sri
Divide radiance into illumination types Li
Ldirect Ldiffuse Ldirect artificial
Lsecondary
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Illumination Types
Natural Illumination
Artificial Illumination
Attenuated
Diffuse
direct
direct
secondary
secondary
Thermal Input
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Solar Illumination
Natural Illumination
Sky Condition Lux direct sun 1 -1.3x105 Full
day(not in sun) 1 - 2x104 overcast
103 Very dark day 102 Twilight 10 Deep
Twilight 1 Full moon 10-1 Quarter
Moon 10-2 Moonless clear 10-3 Moonless
overcast 10-4
direct
.14 w/cm2
?i 0 1.24x105 lux
?i 45 7.6x104 lux
?i 80 1.1x104 lux
?i 90 732 lux
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Solar Illumination
Natural Illumination
direct
.14 w/cm2
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Clear Sky Solar Illumination as a function of
wavelength
.2 .15 .10 .05 .00
Sea level Outside Atmosphere 5,900 deg K black
body
Solar irradiance (W/cm2- ?m)
0 1 2 3 wavelength ( ?m)

Ref Driggers fig 5.13