Light Bounce Strength in GI

The Light Bounce Strength (LBS) determines the reflectivity intensity when a photon hit a surface. Two examples are taken as examples to describe the concepts of LBS in this page.

Example 1

When lighting an object with studio setup lighting, one can see that the global illumination effect is rather weak when the rays of light bounce and submerge into the ambient surrounding.

Thereby one can use the Light Bounce Strength parameter to increase and beautify the GI effect of individual materials and props.

Simply put, use this parameter to strengthen the GI scattering effect of individual props and objects.

1. Make sure there is lighting in the scene that hits upon the object of interest.
2. Under Modify > GI Settings adjust the Light Bounce Strength to control the intensity of GI emitting from the prop.
   
   Note:

   • Higher values in Light Bounce Strength equate to stronger and wider scattering.
   • Zero value in Light Bounce Strength is the same as no GI scattering at all.

Example 2

Usage:

When GI and Light Bounce Strength in the IBL is turned on at the same time and the distances between neighboring surfaces are too small then lights bounces among them repetitively, which causes light blooms in these close quarters.

The problem where surfaces in close proximity has a tendency to increase the GI bounce rate. This can cause the said surfaces and thereby the object to over-expose and become overly luminous. Light Bounce Strength can be utilized to pair down this phenomenon to remedy the resultant visual artifacts. Please click Here to view the project before / after comparison with the LBS parameter decreased from 1.00 to 0.20.

The following is a comparison chart of LBS versus Glow / Self-Illumination Scale.