9.5.2

688 • CHAPTER 13
RENDERING • RENDER SETTINGS • 689
3. 32-Bit formats (in particular the HDR formats: HDR (Radiance) and OpenEXR)
are good for use as so-called “Image Based Lighting”, i.e. the lighting of scenes
via GI (only with the Advanced Render module), exclusively with textures,
without the use of light sources.
The “classic” HDR formats
Both of the “classic” (whereby the term “classic” is relative in the fast-moving IT world) HDR formats,
Radiance (HDR) and OpenEXR, that are used in numerous rendering pipelines, are now supported by
CINEMA 4D.
Radiance HDR is the older of the two formats and will most likely eventually be replaced by OpenEXR.
Even though OpenEXR exhibits less dynamic breadth compared to HDR (Radiance) (which is basically
irrelevant in everyday use, otherwise OpenEXR wouldn’t be used in so many Hollywood productions),
it can be compressed to a much smaller le size.
Radiance (HDR)
HDR lets you save in a special 32-Bit pro pixel mode. Radiance HDR possesses vast dynamic breadth,
much greater than in nature. This is why HDR les are often very large. Nevertheless, most HDR texture
libraries are available in the Radiance (HDR) format.
OpenEXR
This format was developed by ILM (Industrial Light & Magic) and can be compressed to a high degree,
despite its wide dynamic breadth.
Clicking on “Options” will make the following options available:
With these options, you can select from different types of compression.
In general:
 Piz-based wavelet does the best job of compressing conventional images.
We recommend you use this format.