[MR] detailed discussion of period optics

[Michelle L. McDaniel]

Hey all!

I don't know how many of you have heard about this book and website, but I
got it at work and thought I'd pass it on, as it was really interesting.

Secret Knowledge: The lost techniques of the old masters 
  http://www.optics.arizona.edu/ssd/FAQ.html 

This discusses the use of various optical devices (concave and convex
lenses, etc.) to aid the painting of many well-known Renaissance pictures.

This is of interest to lots of people because there are links to photos of
the paintings mentioned throughout the website, that are fairly crisp, so
costuming details are easily discernable.

Anyway, y'all take care and don't panic too much in this week before
Pennsic. See some of you there!

**aelfwynn of whitby**