Digital Creative Blog Articles
Optical Sound Optically
NEW Process for Optical Sound Films
By Advent Media, Inc. Webmaster on
Play the video below and listen for what’s not there…
There’s no projector sound, no amplifier noise, no warble in tone. In my 50+ years of being in this business, since my school days, this is the cleanest sound ever from 16mm optical sound.
Optical sound is a marvelous 1930s invention that enabled filmmakers to record a soundtrack as varying waveforms or densitites on a portion of the film. In 16mm it goes along one edge of the film where the second set of sprocket holes would be if it were a silent film. In the projector a light bulb (exciter lamp) focuses a narrow beam of light through that area of the film, and a photo sensor converts it into an analog electrical signal that is amplified and sent to the speaker.
Not satisfied with screen transfers, we invested in a Retroscan Mark II frame-by-frame film high-resolution film scanner to safely capture film without running it through a projector. This yielded far superior visual transfers (now up to 4K images), but to capture sound we still had to run the film through a projector and capture sound through the external speaker jack. That introduced amplifier noise and other distortions from the machinery.
That was until we discovered an open-source software program called AEO-Light, developed by the University of South Carolina, in collaboration with the National Endowment for the Humanities. With the Retroscan, we’re now able to capture the soundtrack along with the picture optically. This software scans the soundtrack area to deliver a super-high-resolution sound file that’s always in-sync with the picture.
If you have old 16mm or 8mm optical sound films that you need digitized, this is the system to use. We have it all tuned up and ready to go.
Request a free quote today!
NOTE: The above Williamsburg films were badly faded color prints, missing all blue dyes and much of the green. This is an example of color correction or conversion to monochrome.