[Radiance-general] dynamic range - RGBE

[Despina Michael]

Thanks again,

well..  I have a couple questions again, on this
1. In the paper "High Dynamic Range Image Encodings" is mentioned that RGBE 
format cannot cover the visible gamut.
I can not understand this since RGBE supports 76 order of magnitudes and our 
eye can see luminances between 10 ^ 6 - 10 ^-7 that is ontly 13 orders of 
Magnitudes.
The only thing that I can think is that propaply RGBE can not encode small 
steps of change for luminance. Is that the reason that RGBE cannot cover the 
visible gamut?

2. and my second question is what we mean by relative precision of an hdr 
image format? Is the smallest step (change of lumminance) that format 
supports? (and why we measure it in %?)
If it is so, when the value of relative precision is greater means that we 
have greater precision (smaller step) or the opposite?


Despina