3e11d9a8$1@news.povray.org...
> Can we assume that your sky from Terragen has a realistic fading; i.e. not
> too strong contrast between sun-position and opposite position? Because I
> still doubt that there is any benefit in using the HDR format with a sky
> picture.

One interesting thing is to look at the color numbers displayed at the
bottom of HDRShop. In the case of Martial's HDR map, the
values are comprised in a narrow and low range (between rgb 0.1 and 0.45),
so in fact no real HDR effect can be expected.
Using the HDR export plugin for Terragen, I obtained a much larger range in
a sunset image, from rgb 0.3 to 166 (on the sun itself), similar to the one
observed in actual HDR probes. Of course these numbers are relative but
playing with the exposure feature in HDRShop allows to see what the image
can reveal. For instance, the HDR park map I used on the Parrott's folly pic
has a range going from rgb 1 to 5 in the "white sky" part, which means that
it's much more directional than the corresponding low range image would
suggest, which is rgb 1 for all the sky parts. The brightest spot is
actually just above the trees. So it's there... which doesn't mean that the
contribution is visually significant !

G.


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