I'm having issues with spotlights and emmiting media where I get black 
dots in the media with a spotlight.

If I comment out the spotlight line then it renders fine.

I was messing about with lightsys but eventually simplified the scene to 
this. I don't really need a spotlight but was wondering if anyone could 
cast any light on this?

-----------
light_source{ y*30 color rgb 1
   //comment out the following line to get it to render ok
   spotlight radius 90 falloff 90 tightness 1 point_at y*-1

}

camera {
   location  <0, 2, -2.0>
   right     x*image_width/image_height
   look_at 0
}

plane {
   y, -1
   pigment { color rgb 0.5 }
}

sphere {  0, 1
    hollow
    texture {
       pigment { rgbt 1}
       finish { ambient 0 diffuse 0  }
    }
    interior {
       media {
          intervals 3
          emission 0.5
          density { spherical }
       }
    }
}
-----------------

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Verm nous apporta ses lumieres en ce 09/02/2006 16:10:
> I'm having issues with spotlights and emmiting media where I get black 
> dots in the media with a spotlight.
> 
> If I comment out the spotlight line then it renders fine.
> 
> I was messing about with lightsys but eventually simplified the scene to 
> this. I don't really need a spotlight but was wondering if anyone could 
> cast any light on this?
> 
> -----------
> light_source{ y*30 color rgb 1
>   //comment out the following line to get it to render ok
>   spotlight radius 90 falloff 90 tightness 1 point_at y*-1
> 
> }
> 
> camera {
>   location  <0, 2, -2.0>
>   right     x*image_width/image_height
>   look_at 0
> }
> 
> plane {
>   y, -1
>   pigment { color rgb 0.5 }
> }
> 
> sphere {  0, 1
>    hollow
>    texture {
>       pigment { rgbt 1}
>       finish { ambient 0 diffuse 0  }
>    }
>    interior {
>       media {
>          intervals 3
>          emission 0.5
>          density { spherical }
>       }
>    }
> }
> -----------------
Just did a test render with and without the spotlight, and both are identical. NO
black dot at all. 
Using both 3.6 and 3.7 beta at resolution of 1024*768 and 1800*1800.

-- 
Alain
-------------------------------------------------
'hAS ANYONE SEEN MY cAPSLOCK KEY?'

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Verm <pov### [at] thirteeendynucom> wrote:
> I'm having issues with spotlights and emmiting media where I get black
> dots in the media with a spotlight.
>
> If I comment out the spotlight line then it renders fine.
>
> I was messing about with lightsys but eventually simplified the scene to
> this. I don't really need a spotlight but was wondering if anyone could
> cast any light on this?
>

I had a look and see your problem.
What you are seeing is a coincident surface type problem.  This relates to
the fact that your spotlight radius and falloff are the same.  If you make
them different (even very minutely - 89.9999) it should go away.

> -----------
> light_source{ y*30 color rgb 1
>    //comment out the following line to get it to render ok
>    spotlight radius 90 falloff 90 tightness 1 point_at y*-1
>
> }

-tgq

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Trevor G Quayle wrote:
> Verm <pov### [at] thirteeendynucom> wrote:
> 
>>I'm having issues with spotlights and emmiting media where I get black
>>dots in the media with a spotlight.
>>
>>If I comment out the spotlight line then it renders fine.
>>
>>I was messing about with lightsys but eventually simplified the scene to
>>this. I don't really need a spotlight but was wondering if anyone could
>>cast any light on this?
>>
> 
> 
> I had a look and see your problem.
> What you are seeing is a coincident surface type problem.  This relates to
> the fact that your spotlight radius and falloff are the same.  If you make
> them different (even very minutely - 89.9999) it should go away.
> 
ahha doh didn't think of that thanks.

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On Thu, 09 Feb 2006 21:10:17 +0000, Verm <pov### [at] thirteeendynucom>
wrote:

>I'm having issues with spotlights and emmiting media where I get black 
>dots in the media with a spotlight.

I've had problems with spotlights and emitting media as well. I posted
an animation and a image but no one picked up on it. My problem
occurred when the camera was very close to the spotlight. It looked to
me as if the cone of the spot was acting as a magnifier.

In povray.binaries.animations
The Curious (co) Incident of the Cam in the Light. - density03b2x.mpg

And in povray.binaries.images
Guessing game - density08c2X.png

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