Red & Far-Red Filters

[Deborah A. Cook]

Most major metropolitan areas have theatrical supply companies.  If you
don't live in such a place, get to know your colleagues in theater
arts.  You might be able to use the scraps from the gel sheets or find
out where they get them.  These filters (gels) come in about 17" x 21"
sheets or in rolls.  The last time I bought them there were about
$6/sheet.  Since they come in such a wide variety of colors, you could
do a lot of strange light and photosynthesis experiments with them.

Deb Cook Ph.D.
Clark Atlanta University