[Radiance-general] diffuse + specular > total reflectance?

[Lars O. Grobe]

Hi,

as this may be because of some standards that I am not aware of, I have 
a question about a record of material properties that I do not 
understand yet.

I have a high reflective surface, and the manufacturer gives me these:

reflectance specular   60 degree: 82
reflectance diffuse:                        10
reflectance total (ASTM E1651):   86

If I add 82 and 10 I get 92 > 86 for the total reflectance. So what does 
this mean, are the values related to the way the reflectance is measured 
and calculated using different procedures according to standards?

CU Lars.
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