> My monitor gamma seems to be in order (around 2.2).

The problem with most monitors is that they are not actually programmed 
exactly with a gamma curve, it's usually something approximating a gamma 
curve, but typically goes off at the black and white ends.  Of course you 
also need to check your monitor settings, things like "brightness" and 
"contrast" can really screw up the "gamma" curve.

> Now I have to figure out a better way to define object color. As
> specifying it RGB= 180,100,100 gives a totally different output. Idea, I
> could just do a inverse gamma correction to those values first....and
> yes, it seems to work just right.

Yes, this is an area where POV also (used to?) do things wrong.  When the 
user inputs a colour, or texture, that data is already in gamma-corrected 
colour space (because they see the colour on their monitor).  You need to 
inverse-gamma-correct that colour/texture FIRST, before you do any 
raytracing, because your raytracer must work in linear colour space.  At the 
very very end you can gamma correct the raytraced image to show on a 
monitor.

IIRC POV doesn't/didn't inverse-gamma-correct textures, which is why the 
colours often came out weird unless you used gamma 0.  Maybe this has been 
fixed now I haven't checked.

Post a reply to this message