Hyperion™ TVM supports the latest recommended veiling luminance measures (Lseq) as well as more rudimentary measures (L20), as defined in CIE88:2004 . Research shows that Lseq is superior to L20 in capturing potentially dangerous conditions . Hyperion™ TVM supports the basic L20 measure for backward compatibility with legacy control systems until these have been upgraded with control algorithms for veiling luminance Lseq.
 CIE. 2004. ”Guide for the lighting of road tunnels and underpasses”. CIE technical report 88:2004. Vienna.
 Lindgren, M et al. 2015. ” Traffic Compensated Luminance Estimation”. CIE 2015. Manchester.