> "Edouard"<pov### [at] edouardinfo>  wrote:
>>> Is this one better?
>>
>> The wax looks just right, you can see the sizes just at a glance by the SSLT!
>>
>> Cheers,
>> Edouard.
>
> In this experiment, I intended to make the size of the flame proportional to the
> size of the candle. So, I adjusted the lights powers according to the sizes
> proportionally, ie: *2 for the biggest, *1, *1/2, *1/4 respectively. I don't
> know the law for the illumination of flames wrt their size. I suppose the
> illumination comes from the surface of the flame, and therefore follows a
> quadratic law. My powers are surely wrong for flame powers proportional to the
> flame sizes.
>
> However, in RL, the size of the flame is generally not proportional to the size
> of the candle ...
>
> I also set the fade_distance in the same order of magnitude than the area light
> (twice). I am a bit confused by the fact that the dome is so barely visible,
> despite 4 candles. But, after all, they are small (the biggest is 16 cm high)
> and the dome is 5 metre from there. Maybe relative illuminations are correct.
>

In a flame, the light comes from the whole volume, and the flame is 
essentialy transparent.

Make this test: light a candle and light some other light, place them to 
project the shadow on a wall or similar surface. Now, take a look of the 
shadow of the candle and it's flame. It's only effect on the light 
passing through it is from it's lower than air ior.

Even the flame of a camp fire is essentialy transparent. You see it only 
because the gaz of the flame is incandescent and emit light.
Same thing with the flame from a gaz stove.
Model those flames using emissive media, without absorbtion nor 
scattering media.




Alain

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