I have encountered quite strange behaviour, when using photons specified
with count, reflection and more than one light source with object
consisting of intersection on bunch of planes. Code below is the
simplest one I have managed to show the bug. Change the value of showBug
to false to make see what I am expecting to see and true to see the odd
behaviour, which looks like is multiplies intensity of colors at least
by magnitude of five...

Also commenting out reflection of the main object or either of the light
sources, setting max_trace_lever lower than 6, changing photon
definitions of either light sources or changing the main object to
something else (like sphere of box) makes the bug go away. Same code
rendered in MegaPov 0.7 looks ok.

I am using POV-Ray 3.5 beta 4 on Windows 2000 Professional w/ SP2.

---------------------------------------------------------

#version 3.5;

#declare showBug = true;

global_settings{
  photons{
    #if (showBug = true)
      count 4000
    #else
      spacing 0.7
    #end
  }

  max_trace_level 6
}

camera {
  location  <     -0.200,      -0.300,       3.600>
  sky       <    0.00000,     0.00000,     1.00000>
  up        <        0.0,         0.0,         1.0>
  right     <    1.38192,         0.0,         0.0>
  angle         55
  look_at   <      0.000,       0.000,       0>
}

light_source {
  0*x
  color rgb 0.5
  photons { refraction on reflection on }
  translate <0, 0, 5>
  rotate <45, 0, -120>
}

light_source {
  0*x
  color rgb 0.5
  photons { refraction on reflection on }
  translate <0, 0, 5>
  rotate <-50, 0, -110>
}


#declare Cut = intersection {
  #declare planeCount = 0;
  #while (planeCount < 4)
    plane {
      z, 0
      rotate <-137.75, 0.0, -11.25>
      translate 1.0*y
      rotate <0, 0, -90*planeCount>
    }
    plane {
      z, 0
      rotate <-42.0, 0.0, -11.25>
      translate  <0.0, 1.0, 0.03>
      rotate <0, 0, -90*planeCount>
    }
    #declare planeCount = planeCount +1;
  #end
}

intersection {
  object { Cut }
  material {   
      texture {      
         pigment {
           color rgbf <0.2, 1, 0.1, 0.97>
         }      
         finish {
            reflection { 0.02 }
         }
      }   
  }
  
  photons {
    target
  }
}

plane {
  z,0
  material {
    texture {
      pigment { rgb <0.8, 0.8, 0.8> }
    }
  }
  translate  -0.851*z   
}

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