to make shadows not physically correct

[blastered_cg]

Hi all Vfr users;

i want to share smth i accidentaly find.

if you set a light whichs color is black (RGB 0,0,0) then VfR calculates this light as some kind of shadow maker.

this is not pysically correct of course but sometimes my renders need a little bit darker shadows. Even bright areas need shadows sometime to get what is the geometry.

I want to repeat that again this is not pysically possible nor correct.

Bye.

[dalomar_cg]

Re: to make shadows not physically correct

Are you asking if you can do that or telling people that you can?...and if you already are, are you reporting that as a bug??

I've know about that trick for a while as a way to make a "shadow light". This is something that is know in digital artist circles for a while, so if the trick works, then go ahead.

[blastered_cg]

Re: to make shadows not physically correct

if it is a bug please do not fix that one :P

i am not much in this CG cicle for long time. i will learn little by little.

[Micha_cg]

Re: to make shadows not physically correct

Interesting, could you show an example - I try it, but don't get it. What light type show this effect?

It could be nice if lights could bet set with negativ multipliers for light removing. Thats the classical CG trick I know, but never have seen.

[dalomar_cg]

Re: to make shadows not physically correct

Interesting that you say that Micha, cause thats the actual trick that I'm familiar with...setting 2 lights in the exact same place, one positive and one negative, so that you can just get shadows.

IMO, this really comes from the days of slow raytracing and unoptimized rendering algorithms. Days when everything had to be managed so that render times would be respectable. Days when getting realistic output took a lot of tweeking and a lot of work. Those days are largely gone, so the need for a trick like this is less and less. But its still nice to have it in your bag if you need it.

I haven't actually tried this with vray (although I used to use it in MAX), but I'll see what I can come up with.

[blastered_cg]

Re: to make shadows not physically correct

Hi;
i tried to recreate the "shadow emitter light" thing to post some renders but unfortunately i made a mistake to think that a light emits shadow. i realise that what i did was only block light rays by using an area light as a VraySkp2sided mtl which can be seen from only one side and dont allow light pass through other side. which means there is no "shadow emitter light" in VfR.
i hope Dalomar will take care of that so we can create shadows. should i write that to wishlist?

[Micha_cg]

Re: to make shadows not physically correct

Maybe Joe can change the input range of the intensity and it works.