Learn how to reduce noise and fireflies with caustics in Cycles
In this quick tip learn how to use the Light Paths node in Blender’s Cycles render engine to drastically reduce noise and fireflies when rendering with caustics. Normally caustics cause a lot of noise, and thus require a high number of samples to get a clean image. Because of this we commonly disable caustics to speed up the render times and get cleaner images. However, caustics also contribute a lot to the realism of a render as they are responsible for color bleed from bounce lighting.
By using Blender’s Light Path node to mix a glossy and diffuse shader we can drastically reduce the noise, keep caustics enabled, and produce a nicer image.