now first off we’ll create some materials, so get into the material editor and seleect a new material, change it it vray material
- change reflection and refraction color to white
- check Fresnel reflections
- choose a very licht blue color as Fog color
- set fog multi. to 0.01
- check Affect shadows

assign it to the torus knot

now create a other material, also a vray material
for diffuse color select a light grey

and if you render you have something like this :

Wellllll one other then,
this time some caustics

first off download the scene :

Download Scene here - Download HDRI here

next start max, load the scene if max asked about a missing HDR image, goto the material editor and correct the path.

i setup the scene, create a box, and a torus knot
added a spot light
- shadows on (vray shadows)
- under vray parameters check the smooth surface shadows

i’m not gonna explain everything what i did, you can see for you self if you download the scene

and render the scene out, you should have something like :

now we are missing the caustics, here we go:
get your vray renderer and goto vray:system
click light settings and select spot01

click “generate caustics” on
subdivs : 2500
multi : 100000.0

now go back to the render dialog and search for vray:caustic tab
click “on”
multi. : 4
search dist. : 0.4
max photon : 2000

and render it out you should get something like :

to get some better caustics change to
multi. : 2
search dist. : 0.4
max photon : 2500
also change the under vray:system -> lightsettings > spot01 caustics subdive to 5000

also add a meshsmooth to the torus (render Iter. 2)

then render it out

this is gonna take long, calculating the caustics but well,

and well thats it
hope this has been usefull

-----------------------------------The End--------------------------------------