Solid Angle's Arnold is one of the visual effects industry's top render engines. Since it's initial release in 1999 Arnold has been used on countless commercials, feature animations and movies, including being used on 7 of the 10 films including being used on 7 of the 10 films currently on the short list for the Visual Effects Oscar "bake off". It was the sole renderer used on Gravity, and primary renderer on Pacific Rim, Star Trek into Darkness and The Lone Ranger, as well as being used for large sections of Elysium, Iron Man 3, and Thor: The Dark World.
Arnold is a full Ray Traced / Global Illumination solution, Physically-Based and utilizes Monte Carlo Path Tracing technique. This brute force approach enables Arnold to handle very large geometry sets quickly and efficiently, unlike other renderers which need to cache out Photon Maps or Point Clouds before the render can even begin. For example Arnold rendered upwards of 1 million lights (for the TV show 'Skins', VFX by The Mill) and a staggering 5 trillion polygons for the space station in Elysium (VFX by Whiskey Tree).
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