English: A 3D rendered image using path tracing, rendered by Blender's Cycles renderer.

The smoothness of the meshes used for the cows has been increased using subdivision. The scene uses very simple lighting, and uniform background colors, to make it easier to interpret differences in global illumination when comparing to versions of the image rendered using different techniques.

2000 light paths were sampled per pixel, but there is still noise in the shadow areas, and a few unwanted bright pixels still appear (known colloquially as "fireflies"). (The noise and bright pixels can be cleaned up using a denoiser, although it may cause artifacts or excessive smoothing.) The image shows plausible bright areas (caustics) caused by light passing through the transparent cow or reflecting from the mirrored cow, but they are blurry because the path tracer needs to simulate slightly rough surfaces when computing the illumination, otherwise too few rays will be captured for the caustics and they will not show up. The image took 26 minutes to render using a recent GPU for acceleration.