clipka <ano### [at] anonymousorg> wrote:
> Am 17.03.2018 um 15:39 schrieb Kenneth:

> > This probably still amounts to 'tweaking'-- but unless there's a remaining
> > technical problem, it works for me.
>
> It remains tweaking indeed: This approach still breaks some (realistic)
> brightness balance - namely that between radiosity and specular reflections.

:-(   As the old Yiddish saying says, "Oy Vey!"  :-P

I'm beginning to think that the only way to get a truly 'realistic' radiosity
render is to use an HDR light probe for the sky, with no additional light
sources... in which case, POV-Ray itself works with all the correct values(?)
and in the correct way.

Otherwise, it seems that using a LOW-dynamic-range sky + light_source(s)
requires *some* kind of tweaking (of one subtle thing or another).. yet which
still works against the radiosity mechanism, if only in a technical sense.

My desire to increase the contrast of a rad scene-- if I feel that it's
necessary-- looks like a no-win situation (except in the HDR light probe case).
Unless I simply postpone that step, and do it later as a post-processing effect
in another graphics app.

> Radiosity and diffuse are mutually balanced automatically (if you don't
> tamper with radiosity brightness...

*That* is a key insight that I've been wondering about. I hope I understand it
(as it relates to a LOW-dynamic-range sky set-up):

Given:
radiosity{brightness 1.0}
light_source{rgb .7}
object{... pigment{rgb <.3,.5,.7> finish{diffuse 1.0}}

Does the 'automatic balancing' keep the object surface color at <.3,.5,.7>
(depending of course on the angle-of-incidence of the light source hitting it)?
Or does my diffuse setting need to be manually reduced, to keep the color from
washing out to, say, <.6,1.0,1.2> (just as a conceptual idea, not real math). Or
am I still clueless about what 'automatic balancing means? :-O

Post a reply to this message