Reference/Release Notes/2.93/Cycles

= Blender 2.93: Cycles =

OpenColorIO 2.0
OpenColorIO has been upgraded to version 2.0. This brings support for reading new OpenColorIO v2 configurations, and improved color management accuracy in the 3D viewport. 

OpenImageDenoise 1.3
OpenImageDenoise 1.3 improves the sharpness of fine details and gives less blurry results.

Subsurface Scattering
Random Walk subsurface scattering now uses Dwivedi guiding to reduce noise. 



Light Spread Angle
Area lights now have a Spread angle, to simulate the effect of a honeycomb or grid placed in front of a softbox. At 180° the area light is a diffuse emitter as before, at lower angles the light is more focused. 

Other

 * Access geometry node attributes on meshes, using the Attribute shader node..
 * New Persistent Data option, to speed up animation renders and re-renders, at the cost of increased memory usage. If this option is enabled, the Cycles render data is cached between animation frames and re-renders. This replaces the Persistent Images option, which was removed. In scene with expensive modifiers, heavy geometry, many images, this can significantly speed up overall rendering time, but one must be careful in heavy scenes to avoid running out of memory.
 * New Light Paths > Fast GI Approximation panel and setting, with convenient access to the AO bounces feature. This was previously part of the Simplify panel and somewhat difficult to find. This feature approximates indirect light with ambient occlusion after a specified number of bounces, which is particularly useful for viewport render previews or final renders where some reduced quality is acceptable.