Unbiased rendering
Prisms by Silverwing

Indigo is famously accurate at simulating the flow of light to render realistic images. Not only does it produce better results, it also makes Indigo easier to use since there are less settings to tune, and there's no need to manually try creating effects like dispersion and fresnel reflections.

Render engine

Spectral rendering

Unlike most renderers which work with RGB colours, Indigo uses spectral colour throughout, from the physically-based sky model to the reflective and refractive properties of materials.

Among other things, this makes it possible to render transparent materials like glass and water at the highest degree of realism.

Metropolis Light Transport

MLT helps most in scenes with complex illumination, where unbiased rendering traditionally struggles to capture important illumination effects. Instead of spreading computational power evenly, MLT concentrates effort where it gives the greatest contribution to the final image. This powerful approach lets you apply the unparalleled accuracy of unbiased rendering to real-world scenes.

Optimised for maximum quality

Indigo's CPU engine runs with a ray depth of many thousands by default.

While other, biased renderers commonly use a default of around 4-8 bounces and would struggle with a setting that high, Indigo is purpose-built for it and delivers great performance.
Diamonds by Silverwing

Material models

True-to-life materials

The material models are completely based on the laws of physics. Realistic fresnel reflections are always on, glossy and transparent materials have an IOR (index of refraction) parameter to control how they interact with light, and there's a whole array of lab tested metals to choose from. Rendering a completely accurate copper or aluminium material is always a just a mouse-click away.

Subsurface scattering

Indigo's unbiased, multiple scattering SSS is efficiently and accurately simulated, for extremely lifelike rendering of skin, wax, atmospheric effects and other light scattering media.

You can use uniform or wavelength dependent scattering, control phase functions, and use homogenous or heterogenous media.

Planet-scale atmospheric simulation

Unlike other rendering systems which rely on so-called practical models based on approximations, Indigo's sun and sky system is derived directly from physical principles. Using Rayleigh/Mie scattering and data sourced from NASA, Indigo's atmospheric simulation is highly accurate. It's stored with full spectral information, and allows fast rendering and real-time changes of sun position.