POV-Ray : Newsgroups : povray.general : Shadows and lighting with HDR sky : Re: Shadows and lighting with HDR sky Server Time
27 Nov 2021 19:01:08 EST (-0500)
  Re: Shadows and lighting with HDR sky  
From: Alain Martel
Date: 28 Sep 2021 11:27:14
Message: <61533452$1@news.povray.org>

> Hello,
> 
> I have trouble getting the lighting right for an outdoor scene. I use an HDR
> sky, radiosity and a ground plane. In this image, it appears that the sky casts
> light onto the box from the left, but there are no shadows.
> 
> Also, the white plane is too dark.
> 
> The HDR sky is https://polyhaven.com/a/lilienstein. The relevant part of the
> code is
> 
> 
> global_settings {
>      radiosity {
>        pretrace_end 0.001
>        count 500
> 
>        recursion_limit 1
> 
>        low_error_factor 0.2
>        brightness 1
>     }
> }
> 
You are using the default error_bound of 1.8.
Try using a smaller value, like 0.5 and see if the shadows are visible.

global_settings {
     radiosity {
       pretrace_end 0.001
       count 500

       recursion_limit 1
	error_bound 0.5 // Should give sharper shadows
       low_error_factor 0.4
// With a smaller error_bound, it can be set larger
       // brightness 1 Not needed as it's the default
    }
}

Another thing to check : Where is the Sun in the sky. Try another HDR 
with the Sun closer to the horizon.


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