Hello, We want to talk about 3D rendering. There are so many people out there struggling with 3D Renderings. so, We want to give out some Information that could hopefully get you guys up to speed and running.

So, we have two types of renders:

Biased Render Engine:

What a Biased Render Engine actually means is pre-computing a lot of information before sending out rays from the camera. In more simple words, It uses an optimization algorithm to greatly speed up the render time, but doing so is not strictly just modeling the physics of light but it is giving an approximation.

Biased means “Limited”–and you set the limit.

Example of Biased Render Engine:

  • V-Ray
  • Redshift
  • Mental Ray
  • Render Man
  • Micropolygon

V-Ray is a pure raytracer, So everything is raytraced, and it is a hybrid renderer, using biased and unbiased rendering methods.

Interior Render Using Vray by Arpit Pandey

Redshift uses approximation and interpolation techniques to achieve quality renders in less amount of time than any other Unbiased render engine and the speed & quality of Redshift are quite amazing. The most important feature of Redshift which is really amazing is that it lets you render massive scenes which may not even fit on the VRAM on your video card.

Pros of Biased Render Engine:

  • More control
  • Superior render speed
  • You can predict the render times.

Unbiased Render Engine:

Unbiased Render Engine means that it has hard factual information that is being pushed through into the processor to figure out the information and a lot of cheating not occurring. To make it simple ” An Unbiased Render Engine takes absolutely no shortcuts in its calculations of calculating rays.”

Unbiased render engines often produce exceptional render quality. Of course, the downside is that rendering speed is an issue.

The most common misconception about unbiased rendering is that it is more physically accurate than biased rendering, but the truth is both are inaccurate. Just the idea of using BRDF such as Blinn or GGX is in itself an approximation of a real-world Material.

Most of the film Industry uses UnBiased Render Engine.

Example of UnBiased Render Engine:

  • Arnold
  • Maxwell
  • Octane
  • Indigo
  • FStorm

Maxwell Renderer is, theoretically, the most accurate, unbiased engine out there. It is more or less designed to simulate the physics behind an IRL camera.

V-Ray has a PPT (progressive path tracing) feature that somewhat simulates an unbiased renderer, but not quite, and there are limitations on what kind of shading level you can achieve with it (so there’s a chance you won’t be able to render out a true noise-free image).

Thea Render has both biased and unbiased rendering engines, which all share the same material system. Thea is maybe 80% the renderer that Maxwell is. The fact that you can switch engines really easily and not have to retexture everything is pretty handy though.

FStorm is a new UnBiased GPU render engine that is developed by Andrey Kozlov. At the moment FStorm is only available for 3Ds Max, but the other 3D software will be supported in the future. However, FStorm shares a very interesting story with Octane as it was none other than Andrey Kozlov a.k.a Karba who was previously known as a developer of Octane developed FStorm. He was responsible for many of the most important features in Octanes like displacement, bloom/glare, volumetric light/fog, QMC sampling, BRDF model, and several others, and he was also responsible for the 3ds Max plugin. Rumor told me that he had left the Octane team, Then suddenly, FStorm comes along like a lightning bolt from clear skies.

There are many others, but We’ve never tried them. We only deal with V-Ray on a daily basis.

What is better? Biased or unbiased?

Most renders use solutions that make their render biased, even if they call it unbiased. If they didn’t, the process would be extremely slow. Biased engines are very intelligent; in that, they are the most efficient way of getting a correct image. In fact, you can almost call unbiased inefficient.

Long story short: if you are doing true scientific physical calculations and have a ton of computational power and time, unbiased may serve you well. If you are interested in rendering physically accurate images in a reasonable amount of time, biased solutions will get you there faster. Chances are you are already doing this no matter what rendering engine you are using.

We hope this helps people choose their own favorite Render Solutions.

Happy Rendering, Thank you.