Photoréalisme : les points importants

This article summarizes the most interesting points made in the following video:

75% of images in IKEA’s are in fact photorealistic CG images (and no photographs).

CG offers greater flexibility. They most importantly allow to visualize objetcts that do not exist yet.

There are 4 fundamental elements that must be of the utmost quality to generate realistic CG images: modeling, materials, illumination and post-processing.

The most time-consuming domains are materials and illumination.

…90% of the time, the materials and lighting carry the weight of creating truly photorealism imagery. - Alex Roman, From Bits to Lens

Modeling #

• Use real objects dimensions
• Avoid thin edges (i.e. default generated forms in common DCC)
• Use real references when modeling 3D objects
• You need excellent anatomy knowledge when modeling 3D humans

Materials #

• Use Materials and Shaders that are physically correct
• Use Normal Maps and Bump Maps to simulate small details on surfaces
• Simulate materials imperfections (fingerprints, dust, etc.) with textures

Illumination #

• Use lights similar to real lights : to simulate the sun, it is better to reproduce its real color and direction
• Reflections on materials are very important

Post-Processing #

• Simulate light glares / lens flares
• Simulate Motion Blur
• Depth of field is very important
• Use chromatic aberrations
• Simulate lens distorsions of cameras

Colors and dynamic range #

Following figure (from Blender Guru) shows common cameras sensors sensitivity :

It is important to avoid sRGB (older technique with limited dynamic range). Instead use ACES, an industry standard.