If you want film that is only blue sensitive, it would be better to use a
blue filter over the lens than to try to remove the panchromatic
sensitizing dyes. On the newer films, the chemicals required for color
sensitivity are actually incorporated in the silver crystals, so it would
be extremely difficult, if not impossible, to change the crystal structure!
Another possibility would be to use positive film, which is sensitive
mainly in the blue area.
Sil Horwitz, FPSA
Technical Editor, PSA Journal
silh@iag.net
Visit http://www.psa-photo.org/