426a14c0$1@news.povray.org...

> OK. Cos, one of the major problems I constantly have with POV-Ray is the 
> image is too dark, or it's too light, or it looks washed out, or part of 
> it is too bright but the rest is too dark, or......

This problem is quite common in 3D. In fact even big movie productions can 
suffer from it (remember battle in Hulk, where all we could see were grayish 
shapes moving around the screen).

I still plan to write something for the wiki 
(http://www.wikipov.org/ow.asp?SceneLighting) but haven't got around to do 
it. My basic advice would go like this:
- be sure of your gamma settings
- make everything ambient 0. In particular, beware of the default ambient 
value in many textures provided with POV-Ray, particularly in textures.inc, 
metals.inc, woods.inc stones1.inc and stones2.inc. The non-zero ambient in 
these textures is pure legacy, but seems the main reason for having so many 
washed out pics.
- remember that real light is not clamped in the <0,1> range, and that 
neither is POV-Ray. Have a look at Jaime's lightsys macro and tinker with it 
to see the actual values output by the macro. This is often very surprising 
(VERY high intensity values, VERY short fade_distance).
- remember that real lights and real colours are rarely pure, like all white 
or all red. Search for digital images (or better, make your own) and sample 
them.
- use a tool like the Gimp or the color macros in colors.inc to play with 
the HSV colorspace (3.7.3.2 in the POV-Ray docs).
- use radiosity, starting with recursion_limit 1 instead of 2 or 3 (as in 
the scene template). Increase to 2 and higher only if necessary. Too high 
recursion values are the main reason why radiosity scenes are often washed 
out in POV-Ray (some people seem to think that the higher the better).
- and above all, learn about lighting schemes, like the classical 3-point 
lighting, and experiment with them http://www.3drender.com/light/3point.html

> Let's see if Google can do this... ah, yes. Here we go...
http://www.lionking.org/~lynxcat/nimh/brisnico.jpg
>

These links will give you a better idea of what matte paintings are in 
current moviemaking:
http://www.maxdennison.com/
http://www.dusso.com/

G.

Post a reply to this message