> Not sure I understand you.  You say you want a stronger white?
>
> > That's too bad, because I really like the effect
> > in photographs where focal blurred lights produce bright circles.
>
> You mean lens flares?
>

I think I understand what he means and it isn't lens flare.  If you take a
photograph of something and there is a visible lightsource in the background
(assuming that the background is out of focus), the lightsource looks
blurred, but because it is much brighter than the objects around it, it
creates a glowing halo effect.  When creating visible lightsources in POV
you can set a colour value >1, but it gets clipped.  I think what he is
wondering is when you use focal blur, does the colour get clipped before or
after blur sampling?  If it gets clipped after, it would be fine, if before,
then maybe the light colour wouldn't carry enough weight in the blurring and
not look as one should expect.

i.e for simplicity lets look at five numbers averaged:

0.3, 0.5, 0.7, 1.5, 5

clipping after you get:
(0.3+0.5+0.7+1.5+5)/5=1.6 --> 1.0 (clipped)
clipping before you get:
(0.3+0.5+0.7+1+1)/5=0.7

the values greater than 1 lose their appropriate weighting in the average if
they are clipped beforehand

-tgq

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