I think if you double-check this, you'll find it's incorrect. I would like to see the entire quote before I make a boobie of myself, but Farciot Edouart's field of expertise was backscreen projection, not matte work. He was in charge of that at Paramount for about 25 years.

Again, as far as I understand such things, there was no such animal as a "blue backing" matte process in the silent or early sound era. The concept was the same: photographing an element in front of a limbo screen, which then creates the element and a mask-- the "matte"-- to print into another shot. This could be done with either a limbo black background (as Bert Gordon did years later) or a white background. The Dunning process is pretty similar, using (whoa. Where's Jim Aupperle when I need him?) red light to create some sort of differentiation effect between subject and neutral background.

With color, there needed to be a variation on the process. Rather than using contrast, the variation involved knocking a solid color out to produce 1) a solid-black matte to print onto the background plate and 2) an isolated element to print "into" the created "hole" in the background. You'd have an interim element which would be, say, a shot of a jungle with a monster, with a solid black shadow of a man walking by. On another element (after you knock the color out, whether it's blue, yellow, or now, green), you have a black (or absolutely transparent) element with just the walking man on it. Finally you print one into the other.

The "blue backing" refers to the deep blue cyclorama hanging at the back of the sound stage. This was developed, I believe, for an English film circa 1954. [edit: actually first developed by Larry Butler for Thief of Bagdad in 1940, but rarely used until the 50s.] In the 50s came Rank's "yellow screen" or "sodium" process, basically a more precise variation. Disney bought the rights and the specialized prismatic lenses it needed for the process. The lenses disintegrated over time and no one ever created new ones.

ps.
http://books.google.com/books?id=lvUJyB5R660C&pg=PA198&lpg=PA198&dq=%22blue+backing%22+effects&source=bl&ots=lguMq1JY__&sig=zEebEXR2ZqE70vXRdFjdlY7YLq8&hl=en&ei=mGGcS4zQEojUsQOyvq2_Aw&sa=X&oi=book_result&ct=result&resnum=3&ved=0CBAQ6AEwAg#v=onepage&q=%22blue%20backing%22%20effects&f=false

see pp 192-193. Explains it all better than I do. 

Last Edited By: Ted Newsom Mar 14 10 12:18 AM. Edited 3 times.