Hi:

I like using variable-density analog B&W monoaural negative [no
positive and no "reversal"; just the negatives] film optical tracks for
audio. The audio characteristics of the film make my mouth-water. Yes,
for some wierd reason, the film's audio makes me hungry. To add to the
delicous audio quality , I would like to coat the film with bad-butter*
and tiny traces of bitminous and anthracite coals before recording.
After recording, I would like to clean it in a dark environment and
then develop the clean film.

Audio signal, in the form of light changing its intensity in a
analogous manner to the sound, is shined onto a negative film. The film
is developed and playback is accomplished by shining light of a
constant intensity onto the developed film. As the light goes through
the film, the patterns on the film will change the intensity of the
light that is received by a photoelectric cell. The change in light
intensity results in a changing electric current which is sent into an
amplifier and then to a loudspeaker.

http://www.mtsu.edu/~smpte/twenties.html

"The Tri Ergon Process uses a technology known as variable density,
which differed from a later process known as variable area. The Tri
Ergon process had a pattented flywheel mechanism on a sprocket which
prevented variations in film speed. This flywheel helped prevent
distortion of the audio. Tri Ergon relied on the use of a
photo-electric cell to transduce mechanicalsound vibrations into
electrical waveforms and then convert the electrical waveforms into
light waves. These light waves could then be optically recorded onto
the edge of the film through a photographic process. Another
photo-electric cell could then be used to tranduce the waveform on the
film into an electrical waveform during projection. This waveform
could then be amplified and played to the audience in the Theater. The
Fox Film Corporation acquired the rights to the Tri Ergon technology in
1927. "

The ERPI system, Fox-Case's Movietone, and De Forest's Phonofilm use
variable-density recording film audio

*Here is the link which describes how my "bad butter" is made:

http://groups.google.com/group/uk.fo...111377c?hl=en&


Regards,

Radium