scott <sco### [at] scottcom> wrote:
> > These "reflection" numbers in pov-ref.txt file are extracted from a image,which
> > with location and reflective information for 40000 points.We call this image a
> > reflecity image in remote sensing.This image is photoed by flight.Thank you for
> > your advice.I go to have a try!Gratitudes!
>
> I must admit I don't have much experience with OpenEXR output. What
> happens if you render the below scene to OpenEXR and check the
> luminance, what values to you get for different values of "ref"? Do they
> match up?
>
> #version 3.7
> global_settings {assumed_gamma 1}
> #default{ finish{ ambient 0.0 diffuse 1.0 }}
> camera
> {
>   orthographic
>   location z
>   look_at  0
>   right    x*image_width/image_height
> }
> light_source{ <0,0,10> color rgb 1 }
> #local ref = 0.5;
> box { -1/2 1/2 pigment{ color rgb ref} }

I have another confusion:I have known the value of solar irradiance(w/m^2) from
200nm-2200nm,how can I set the solar irradiance in pov?

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"CAS" <sup### [at] cstnetcn> wrote:
> I have another confusion:I have known the value of solar irradiance(w/m^2) from
> 200nm-2200nm,how can I set the solar irradiance in pov?

It is not exactly clear what you are trying to do, but my best guess would be
that you are trying to match POV-Ray output with some physical measurements that
you got somewhere. That is something POV-Ray light models (or that of most
general purpose 3D programs) are not designed to do. You may get much better
results using Radiance (http://radsite.lbl.gov/radiance/HOME.html) or
special-purpose wave-model based ray-tracers.

Thorsten

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"Thorsten Froehlich" <nomail@nomail> wrote:
> "CAS" <sup### [at] cstnetcn> wrote:
> > I have another confusion:I have known the value of solar irradiance(w/m^2) from
> > 200nm-2200nm,how can I set the solar irradiance in pov?
>
> It is not exactly clear what you are trying to do, but my best guess would be
> that you are trying to match POV-Ray output with some physical measurements that
> you got somewhere. That is something POV-Ray light models (or that of most
> general purpose 3D programs) are not designed to do. You may get much better
> results using Radiance (http://radsite.lbl.gov/radiance/HOME.html) or
> special-purpose wave-model based ray-tracers.
>
> Thorsten

Thank you for your help.Yes,what I want is matching POV-Ray output with some
physical measurements.I have used spectral
render.http://www.lilysoft.org/CGI/SR/Spectral%20Render.htm.

#version 3.7;
global_settings{ assumed_gamma 1.0 }
#declare SpectralWavelength =730;
#include "spectral.inc"

camera
{
angle  7.54371
location <camera_x,camera_y,camera_z >
look_at <0,0,0>
rotate <0,-31,0>
right x
up y
}

light_source {<sun_x,sun_y,sun_z>
             SpectralEmission(E_D65)   //some CIE standard illuminants
             }

#declare n = 0;
#fopen   Input_geom_file geom_file_name read
#fopen   Input_spec_file spec_file_name read
#while(defined(Input_geom_file))
    #read(Input_geom_file,x1,y1,z1)
    #read(Input_spec_file,ref)
      box
        {
           -1.55,1.55
           rotate y*-31
           translate <x1-center_x,y1-center_y,z1-center_z>
           pigment {color rgb 1}
           finish {
                 ambient 0
                 diffuse ref
                   }
            }
    #declare n = n + 1;

My solar irradiance in 730nm is 1.33015(w/m^2),and I have converted irradiance
to illuminance with the lm/w in 730nm,then the value of illuminance in 730nm is
0.47262925(cd/m^2).My issue is how can I input the illminance in 730nm?
"light_source {<sun_x,sun_y,sun_z>
             SpectralEmission(E_D65)
             }  "
With this light_source,the illuminance is E_D65.How can I input my illminance?

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