> Hi,
>
> I was using PovRay for two 3d-wallpapers for now. Everthing is scripted (i don't
> like the idea of using pov-ray with models) -- but sadly i had to post-process
> the last one a little.
>
> So .. in the one i uploaded, i had a problem with the reflection .. which is the
> reason, i had to post-process it (blur the reflection; and then also add grain,
> to make the editing less visible -- i didn't like to do that, but i didn't like
> to rerender it either). The problem was, that the volume-light isn't reflected.
> I used media and a reflective plane:
>
> media {
>      scattering { 1, 0.1 }
>
>      intervals 30
>      samples   10,40
>      method    1
>
>      variance   0.5/128
>      confidence 0.95
> }
>
> plane {
>      <0, 1, 0> (-3)
>      pigment { color rgbf <1.0, 1.0, 1.0, 0.0> }
>      finish { reflection 0.3}
> }
>
> so .. for future-images: Is there a way to achieve that?
>

Sampling method 1 and 2 are deprecated. You should use method 3 (the 
default) with only 1 intervals (also the default value).
With this method, samples default to 10 and need to be set to at least 3.
Increase samples as needed. In your case, samples 2000 would probably 
have been faster. I suggest starting with samples 50 and increase if needed.
Only use a single samples value as any second value is simply silently 
ignored.
The paremeter ratio have no object and should be omited.
You can usualy ignore variance and confidance as the default is normaly 
very good.



To get blured reflection, you have 2 options:

Using micro normals: normal perturbation scalled very small. You want 
the normal to be sub-pixel in size.
Using normals{granite 0.2 scale 0.00001} can give good results.
Prefered if you have inter-reflecting objects or objects whitch reflect 
themselves.
May be grany, looks much beter when using antialiasing.

Using macro normals: Use an average of many textures with randomly 
translated normals scaled large to very large. The translate is normaly 
chosen in a range similar to the scaling of the normals.
Usualy looks smooth but will make render time shoot through the roof if 
the object reflect itself or another that also use this method.
The smoothness depends on the number of averaged normals.
Don't need antialiasing.
Render slower in most cases as the whole texture need to be evaluated 
several times and averaged. You can't just average several normals.

Both can be combined, the averaged normal applied to an object with 
no_reflection and the micro normal to an exact copy but with no_image, 
and possibly no_shadow.
This prevent huge slowdowns from cascading reflections while making 
objects with blured reflection still have blured reflection if seen in a 
smooth mirror or through transparent objects.

The blured reflection methods can also be used to create blured refraction.


Personaly, I would have used variable reflection for the ground plane:
reflection{0.1, 0.5}
or
reflection{0.1, 0.5 fresnel} and added interior{ior 1.7}
Adjust the ior value as you want.
I like using fresnel in my reflections.



Alain

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