update on lumen prints

From: Christina Z. Anderson ^lt;[email protected]>
Date: 11/18/05-08:36:23 AM Z
Message-id: <006301c5ec4d$75100bf0$6b6992d8@christinsh8zpi>

Just a quickie,
It's getting to be about the end of the semester and the student doing lumen
prints is wrapping up her project. Thanks to Don Bryant's offlist
generosity (DON what do i owe you for shipping?????) the favorite paper she
says is a single weight Portriga grade 6. I think she means Brovira but
will have to check with her again to make sure it is that, as Don gave us a
stack of all kinds of paper, both being in there. Don, you made this
student's "day" and we both thank you.

Oh, another paper that is beautiful is Forte. Of course. Forte and Bergger
are my faves anyway. Those were not outdated. The RC Forte polywarmtone is
dramatically pink.

The interesting thing I want to report is that there is a remarkable
difference when these single weight papers are held to transmitted light.
It does not happen in the double weights. The dull olive green on the
surface of the paper shows as brilliant violet when held up to light. I am
going to hazard a guess that it is the Mie effect (written about in
Scientific American a couple decades ago) and that the different sizes of
granules and types of granules of silver react differently to overexposure
of the sun and refract color differently, but somehow the ones that refract
violet are behind the olive ones. I can't think of another reason why the
purple shows only with transmitted light so maybe someone else can make a
better guess than that. Whatever the reason, she has decided to display a
few of them in lightbox type frames. Gorgeous possibilities.
bye
chris
Received on Fri Nov 18 08:36:40 2005

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