UV / Black light ? Possible?

[AlexP]

Is it possible in Vray to simulate the effects of a UV light / Black light ?

No, Im not visualising an 80s themed house party

[super gnu]

you need UV-ray. im sure its coming out any day now.

(i cant find the link, seems the fx guide podcast has been removed)

[AlexP]

you need UV-ray.

bravo




cant believe I didnt think of that

[Robert Everhardt]

does it have mushrooms?

couldnt you do it with a falloff map?

[Robert Everhardt]

you need UV-ray. im sure its coming out any day now.

(i cant find the link, seems the fx guide podcast has been removed)

lol. that is very funny

[super gnu]

its not my idea.. was an april-fools presentation done by chaosgroup. doesnt seem to be any trace left of it online though.. and for some reason its not showing up in forum searches.. maybe i dreamed it. in which case.. it is my idea and im going to patent it.

[AlexP]

couldnt you do it with a falloff map?

I guess, but not sure how ?!

[AlexP]

Cmon I cant be the only one who has clients stuck in the 80s.

I dont understand the physics of it, but is it possible within the workings of Vray to create the effect "accurately" or will it need to be cheated?

[super gnu]

well basically youd need a material that becomes self illuminated wherever your uv light hits it.

i dont believe there would be any way to do it "accurately" since you would need ( for a start) colour pickers that go beyond the visible spectrum.. (which is an odd concept) - although i guess you could get around this for a lightsource by specifying the wavelength in nanometers. you would also need a way to specify the fluorescence of a material, and the wavelengths of light that caused it to fluoresce. in the end it would be not so different to the "fake" setup:

as mentioned, falloff map might help, use it in light/shadow mode to mask between normal and self illuminated versions of a material.. linked to a nice deep purple light. however, i dont believe light/shadow mode of falloff map is supported by vray .. so im not sure the best way to proceed.

( due to it not being "Phgysically correct" i believe, but this is a crap excuse imho..)

maybe you could render out a pass of the scene with just that light activated (with gi on for the bounced light too if you want) then use that as a mask on specific materials in your final render to control a transition to self -illuminated.

- or just render out 2 versions of your scene, one lit normally, then the other with all materials self illuminated (or maybe just the diffuse pass might be enough) then mask those two with your lightselect of the "uv" light and get creative in photoshop. that way you can choose where and how much fluorescence to add.

[AlexP]

Hmm interesting. Thanks.
Diffuse render element should be enough following that method I think.