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Hello Elton, 
    There are are few parameters most musums do not consider when designing
a shadow exhibit. The light output spectrum of photograhic strobe units is
designed to the response curve of film. The luminesent material dose not
even respond to either red or green light. Try shinning a red or green LED
onto the material, Now try shinning a Blue or ultra-violet LED on to the
same material. What did you observe? The Luminesent material peak response
is actually in the ultra-voilet region. A photograhic strobe does not
produce enought blue light neccessary for the luminesent material to form a
sharp shadow. What are your choices?
     High pressure strobe bulbes used in airport lighting are a great
choice. High speed strobe unit also produce more blue light. Other concepts
I use to improve the quality of the shadow image. Use a layer of mirrored
plastic under the luminesent
material. Shadow contrast is improved and and a magical depth of shadow
effect appears. Add a optical filter in front of the source that removes
both the red and green content. The human eye will see less total light and
will be able to percieve the shadow better. Use a Ellipsoidal refector to
focuse the light. A point source of light will always produce a better
image. If you incorporate all of these design feartures, individual hairs on
your arm will be visual and in focus and last for 30 or more seconds. Good
luck! If you desire more technical information read Doctor Edgerton's book
on strobes. Most of my experiences came from working on a Edgerton
exhibition in the eary 90s. If you need more ideas please call Roger at
585-338-7001

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