Am 23.11.2015 um 11:41 schrieb Mike Horvath:
> On 11/23/2015 4:42 AM, scott wrote:
>> If MapGamut returns linear RGB values (it looks like it does, I couldn't
>> see anything that indicated it does a rgb->srgb conversion) then you
>> must use the rgb keyword in POV as Alain suggested.
>>
>> The srgb keyword is used to supply colours in srgb space, and POV will
>> then "undo" the srgb gamma correction before using the values
>> internally, which is not what you want in this case. Using rgb will
>> force POV to use the values you supply directly.
>>
> 
> This lightened them up a little, but they are still too desaturated.

You probably need to replace the "ambient" with "emission".

The "ambient" keyword was originally intended as a very simple model for
diffuse illumination from other objects: Even with only one light
source, the shadowed sides of objects aren't completely black, as they
are illuminated by light scattered from other objects. The "ambient"
mechanism models this by simply adding a bit of constant brightness to
an object. (Typical "ambient" values for this purpose would be around 0.1.)

On the other hand, people found that "ambient" could also be used to
model glowing objects, i.e. ones that emit light of their own. (For this
purpose, "ambient" would typically be set to 1.0.)

Enter radiosity. This mechanism is intended to model the same thing that
"ambient" was originally designed for -- light scattered from other
objects -- except that it gives far superior results. So on the one hand
"ambient" is obsolete in scenes with radiosity, and up until 3.6 it
would typically be disabled by either defining the materials to not have
any ambient in the first place, or by setting the global "ambient_light"
to zero to allow re-use of materials designed for non-radiosity scenes.
However, on the other hand, the latter would prevent the use of
"ambient" to model glowing objects.

To solve this dilemma, POV-Ray 3.7 introduced the "emission" keyword,
which now takes over the role of "ambient" for glowing objects, while
the use of "ambient" is now limited to its original role as "poor man's
radiosity", by automatically disabling it whenever radiosity is used.

It seems to me that your original scene didn't use radiosity, so the
"ambient" parameter served both roles there; so now that you have added
radiosity, rather than blindly replacing "ambient 1" with "emission 1"
you will probably have to use a lower value; I think "emission 0.5"
gives good results.

Note however that radiosity messes with the apparent colour of objects,
as it adds some coloured illumination from nearby objects; this may be
undesired in an image intended to represent a colour model, so my
personal recommendation would be to disable radiosity in the scene
again. Alternatively, you may want to set "gray_threshold" to 1.0 to
make radiosity illumination completely colourless.

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