Preset (CineRender Global Illumination)

Presets are available for the optional Global Illumination effect, in the Detailed view of PhotoRendering Settings for the CineRender engine.
Interior spaces are mostly illuminated by fewer, smaller light sources: light that falls through windows, and lamps that emit light within a limited radius. Interior spaces are therefore more difficult to calculate for GI.
Exterior spaces are basically set up under an open sky. Skies emit light evenly from a large surface, which makes it easier for GI to calculate exterior scenes.
Preview: These have reduced values, which can be calculated quickly and are well-suited for test renderings.
High: Designed for higher quality renderings. However, it may be necessary to increase or decrease individual values to achieve the desired render speed/quality.
Custom: As soon as you modify a GI setting, this option will be activated.
Interior - Preview: Uses Irradiance Cache + Radiosity Maps. A fast preview with reduced Diffuse Depth.
Interior - High: Uses Irradiance Cache + Irradiance Cache.
Exterior - Preview: Uses Irradiance Cache + Radiosity Maps. A fast preview with reduced Diffuse Depth.
Exterior - Physical Sky: Uses Irradiance Cache + QMC.
Exterior - HDR Image: Uses Irradiance Cache + QMC.
Preview: These have reduced values, which can be calculated quickly and are well-suited for test renderings.
The difference between Physical Sky and HDR Image: Force Per-Pixel is enabled for the latter. An HDR image assigned to a Sky object is evaluated precisely for rendering, which will more precisely render multiple shadows - if they are present in the HDR image (note that the Diffuse Depth value may have to be increased).
Object Visualization - High: Uses Irradiance Cache + Irradiance Cache.
Progressive - No Prepass: Uses QMC + QMC.