coloured caustics

[whori]

hi everyone...i've seen picture:

simple plane with torus knot...torus knot had material something like this(i guess):

fully refracted...but also coloured ( all rainbow colours, not only one colour), and this image had caustics, which were also coloured..i tried to make something like that adding fog colour..but you can add there only one colour..

i hope you understood what i want to explain and what result i want to get;) i mean colourful caustics...

[Dave Buckley]

can you not just create a rainbow image in photoshop or google one, and then add it as a bit map in the refraction/fog slot???

[whori]

can you not just create a rainbow image in photoshop or google one, and then add it as a bit map in the refraction/fog slot???

i cant put it in fog slot,,,but when i put it in refraction slot,caustics are simply white.

btw im using vray

[Stephen Thomas]

Are you talking about trying to create a dispersion effect i.e. like a prism where the light is split into its component colours? If so this tutorial might help you, there's a sample scene included too.

 

http://www.cgsharpe.com/?p=33

[Dave Buckley]

also what lights are you using??? and can you post examples of your results and the kind of results you are after i have just quickly created this, it is a clear glass material with a gradient ramp in the refraction slot, fog is default, it is lit with 1 vray plane light. if you are using max standard lights, you will find that they won't generate caustics with vray unless you have affect shadows checked on the material and and then it is a fake caustics effect. The caustics in my example are just to show you can achieve what you are after in vray just using gradient ramp in refraction slot. obviously the settings would ned tweaking to get more control over caustic effect

[whori]

Thank You Stephen for this one, it is good also, but i was talking about what Dave has show. Thanks Davem thats exactly what i was talking about.i am attaching image with what i could get..

[Dave Buckley]

Cool so you are able to do it now??? Just have gradient map in refraction colour of clear glass material. Or are you still stuck,it appears that you can now do it from your image

[whori]

Cool so you are able to do it now??? Just have gradient map in refraction colour of clear glass material. Or are you still stuck,it appears that you can now do it from your image

i think i can, but i like your result more;) because it has clean colour on surface..and mines is dotted. but thanks really

[Dave Buckley]

http://www.aversis.be/tutorials/vray/index.htm

those tutorials should help