Glassworks with fake dispersion

Sambor · August 3, 2017, 6:13pm

Here is my personal approach to faking chromatic dispersion with cycles Refraction and Glossy BSDF. I used absorption nodegroup by BlenderDiplom from this tutorial https://www.youtube.com/watch?v=qkqsx951gcg and combined it with a simple idea of using Fresnel node as a factor for alternating the hue of glass tint. It is not perfect, it’s rather a test project and needs many corrections and adjustments, but i believe that tweakin a few value will give you a nice and cheap effect.

glassworks.blend (629 KB)

Sambor · August 3, 2017, 6:31pm

And here a few examples

Huge beer mug type “Einmass” (from german)

without fake dispersion (i’ll call it FD further)

and with FD

As you can see there is just a subtle difference between those 2. Especially in the thick parts of the lug and the bottom of the mug.

Sambor · August 3, 2017, 6:36pm

Another beer mug, this type also has a german name “Stange”
without FD

and with FD

Here the diffence is even smaller, but fake dispersion gives some additional tint in the bottom of the glass, and gives a slightly “rainbow” effect on the lug.

Sambor · August 3, 2017, 6:43pm

I hope noone will accuse me for promoting alcoholism, because the next subject is a whisky glass. It has a nice complex shape with both smooth and sharp transitions.
without FD

and with FD

The difference is almost invisible (tint of reflections on the upper belt) but it gives some extra life to the scene.

Sambor · August 3, 2017, 6:54pm

And finally our favorite Susanne. I guess i don’t have to mark which one is made of clear glass and which has some extra nodes for the material tint added. Although in case we work with a bigger concrete piece of glass i.e. ball or monkeys head this material node gives rather a soap bubble effect.