Red & Far-Red Filters

Gerry Deitzer gd3 at UMAIL.UMD.EDU
Tue Dec 2 10:02:53 EST 1997

Red filters are relatively easy to come by, but remember that not all
are the same.  I use Roscolux #27 Medium Red celophane that I obtain
locally from a theatrical supply company called Kinetic Artistry in
Takoma Park, MD.  Make sure that you use a fluorescent light source
(cool-white is fine) since these are all cut-off filters and all
transmit in the far-red.  Do not use Incandescent bulbs !!  

Far-red filters are the real problem.  The best filter is a Plexiglas
filter that was made by Westlake Plastics in Lenni Mills, PA called
FRF-700.  Unfortunately, they no longer manufacture it and have no more
in inventory.  A suitable alternative is to combine the red filter
described above with a blue filter (Roscolux # 385 - Royal Blue).  In
thism case you want to be sure that you have an adequate supply of
far-red, which cool white does not.  If you wish to match the red
filter, use a wide spectrum gro-lux or vita-lite fluorescent source.  If
you want maximal far-red energy, use an incandescent source, but be
careful of the amount of heat.  You can very easily melt the celophane
and start a fire.  

These filters can be obtained from Rosco Laboratories, Inc., 36 Bush
Ave., Port Chester, NY 10573.  Sorry, I don't have a phone or e-mail for
them, but they might have a web site.

Hope this was helpful.
Gerald F. Deitzer

Alex Enyedi wrote:
> I am looking for the name of a supplier(s) of far-red and red filters
> for use in my Plant Physiology class next semester. I have checked both
> the Carolina and Wards catalog but nothing was available. If you can
> help me out, I would appreciate it.
> Thanks in advance.
> Alexander Enyedi
> Dept of Biological Sciences
> Western Michigan University
> Kalamazoo, MI 49008

More information about the Plant-ed mailing list