The lte term (which the multiplier is scaled by in each iteration of the integrated lighting function, aka "throughput" in pbrt), is greater than one -> images gets lighter and lighter. Intuitively, the multiplier should be shrinking with each bounce.
The lte term (which the multiplier is scaled by in each iteration of the integrated lighting function, aka "throughput" in pbrt), is greater than one -> images gets lighter and lighter. Intuitively, the multiplier should be shrinking with each bounce.