Hi!

I am posting two images, one with radiosity, a point light source, and a
blue sky...other one rendered using hdri map in mlpov without any
conventional light source. After seeing some wonderful images with hdri, I
should say I am a little disappointed with the result....the render with
conventional lighting looks far better. I guess I have used some
inappropriate radiosity parameters. Can anybody please throw some light on
how to improve the image. I am giving the radiosity settings for both the
images.
radiosity setting for conventional lighting:
radiosity {
      pretrace_start 0.08
      pretrace_end   0.04
      count 35

      nearest_count 5
      error_bound 1.8
      recursion_limit 3

      low_error_factor 0.5
      gray_threshold 0.0
      minimum_reuse 0.015
      brightness 1

      adc_bailout 0.01/2
    }

radiosity for hdri
radiosity {
    pretrace_start 0.08           // start pretrace at this size
//To be used with HDRI maps
    pretrace_end   0.04           // end pretrace at this size
    count 50                      // higher -> higher quality (1..1600) [35]
    nearest_count 5               // higher -> higher quality (1..10) [5]
    error_bound 1.8               // higher -> smoother, less accurate [1.8]
    recursion_limit 3             // how much interreflections are
calculated (1..5+) [3]
    low_error_factor .5           // reduce error_bound during last pretrace
step
    gray_threshold 0.0            // increase for weakening colors (0..1)
[0]
    minimum_reuse 0.015           // reuse of old radiosity samples [0.015]
    brightness 1                  // brightness of radiosity effects (0..1)
[1]

    adc_bailout 0.01/2
    normal on                     // take surface normals into account [off]
  }

thanks
sup


"Skip Talbot" <sta### [at] uiucedu> wrote in message
news:3f84d8d7$1@news.povray.org...
> HDRI stands for High Dynamic Range Imaging.  Its basically an image format
> that doesn't have a limit to the brightness levels of the colors.  Mael
> wrote a patched a version of POV 3.5 that reads such a format for use in
> scenes.  Download his patch here:
> http://pov.monde.free.fr/mael/mlpov083.html
> English older version instructions:
> http://martial.rameaux.free.fr/mael/mlpov081eng.html
>
> Run some of the sample scenes to see what it can do and for the syntax.
> There were several posts on this board a few months ago that demo what
HDRI
> can do.  Here's an aircraft I rendered using an HDRI map:
> http://members.aol.com/skipt1/3d/highres/longez6.png
>
> Skip
>
>

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