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LuxRender is a physically based and unbiased rendering engine. Based on state of the art algorithms, LuxRender simulates the flow of light according to physical equations, thus producing realistic images of photographic quality.

PhotoRealistic RenderMan, or PRMan for short, is a proprietary photorealistic RenderMan-compliant renderer.

appleseed is a modern, open source, physically-based rendering engine designed to produce photorealistic images, animations and visual effects. It provides individuals and small studios with an efficient, reliable suite of tools built on robust foundations and open technologies.

Visual Designer is one handy yet efficient tool for 3D real-time photorealistic rendering, on both CPU and GPU (with AMD & NVIDIA GPU support). It is one easy solution to the complicated parameters of the so-called “specialized tools” as it offers an absolutely surprising amalgam of ergonomics and improved workflow. With its lighting-fast speed, you can achieve swifter levels of performance, but also quality ... thanks to its physically correct engine (Unbiased). The ease of workflow that Visual Designer provides you lets you switch between different look variation briskly so that your speed and flow remain in the same productive momentum. »

Thea Render is a state-of-the-art biased/unbiased renderer with a rich set of innovative features, a powerful material system and its own advanced studio, all-in-one. Plugins are available for 3dsMax, Blender, Cinema4D, Rhino, SketchUp and SoftImage.

Sunflow is an open source rendering system for photo-realistic image synthesis. It is written in Java and built around a flexible ray tracing core and an extensible object-oriented design. It was created as a framework for experimenting with global illumination algorithms and new surface shading models.Current Features:

NOX Renderer is a rendering software based on unbiased methods.

Indigo Renderer is an unbiased, physically based and photorealistic renderer which simulates the physics of light to achieve near-perfect image realism. With an advanced physical camera model, a super-realistic materials system and the ability to simulate complex lighting situations through Metropolis Light Transport, Indigo Renderer is capable of producing the highest levels of realism demanded by architectural and product visualization.

Pixie is an open source RenderMan renderer for generating photorealistic images. You can compile Pixie on Windows (using Visual Studio 2005), Linux and on OSX (using XCode or unix style configure script).

Marmoset Toolbag™ is a full-featured, real-time material editor and renderer bundled in a tidy package. Toolbag provides 3D artists a powerful and efficient workflow, bringing exemplary rendering quality to every stage of the 3D art pipeline.

fryrender is the physically-based light simulator developed by RandomControl. It is a photo-realistic render engine where all the elements involved in the generation of the final image (materials, lights and cameras) are based on physically accurate models.

Octane Render is the world's first GPU based, un-biased, physically based renderer. What does that mean? It uses the video card in your computer to render photorealistic results fast...really fast. This allows the user to create stunning works in a fraction of the time of traditional CPU based renderers.