This is the newest of the three raw image formats mentioned here. It
has been developed at SGI, and is included in Sam Leffler's TIFF
Library just as Pixar Log format. It uses 32 bits/pixel and
it is based on human perception, which may have a big advantage in the
future, when more sophisticated devices will be available. The new
proposed format uses log encoding of luminance and 
encoding of chroma. In this way the luminance range covers 38 orders of
magnitude, and chroma covers all visible colors in imperceptible
steps. The relative luminance accuracy is 
and chroma errors
are always under the visible threshold. This format could be the one
that will be extensively used in the future.