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Hi Lars,<br>
<br>
I think that what you want to do is:<br>
<blockquote><total reflectance> - <diffuse reflectance> =
<specular reflectance><br>
<br>
thus<br>
<br>
86 - 10 = 76<br>
</blockquote>
The specular reflectance that is provided is for a measurement at 60
degrees incidence, if I understand this correctly.<br>
<br>
-Jack<br>
<br>
Lars O. Grobe wrote:
<blockquote cite="mid:499BF260.9090600@nus.edu.sg" type="cite">Hi,
<br>
<br>
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.
<br>
<br>
I have a high reflective surface, and the manufacturer gives me these:
<br>
<br>
reflectance specular 60 degree: 82
<br>
reflectance diffuse: 10
<br>
reflectance total (ASTM E1651): 86
<br>
<br>
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?
<br>
<br>
CU Lars.
<br>
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</blockquote>
<br>
<pre class="moz-signature" cols="72">--
# Jack de Valpine
# president
#
# visarc incorporated
# <a class="moz-txt-link-freetext" href="http://www.visarc.com">http://www.visarc.com</a>
#
# channeling technology for superior design and construction
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