John P. Fulton said in an interview with The American Cinematographer (September 1934),
“The wire technique could not be used, for the clothes would look empty, and would hardly move naturally. So we had to recourse to multiple printing-- with variations. Most of these scenes involved other, normal characters, so we photographed these scenes in the normal manner, but without any trace of the invisible man. All of the action, of course, had to be carefully timed, as in any sort of double-exposure work. This negative was then developed in the normal manner.
Then the special-process work began. We used a
completely black set – walled and floored with black velvet, to be as nearly
non-reflective as possible. Our actor was garbed from head to foot in black
velvet tights, with black gloves, and a black headpiece rather like a driver’s
helmet. Over this, he wore whatever clothes might be required. This gave us a picture
of the unsupported clothes moving around on a dead black field. From this negative, we made a print, and a duplicate negative which we intensified to serve as mattes for printing. Then, with an ordinary printer, we proceeded to make our composite: First we printed from the positive of the background and the normal action, using the intensified, negative matte to mask off the area where our invisible man's clothing was to move. Then we printed again, using the positive matte to shield the already printed area, and printing in the moving clothes from our "trick" negative." This printing operation made our duplicate, composite negative to be used in printing the final master prints of the picture” (Weaver et al 82).
From Universal Horrors: the studio's classic films, 1931-1946. By Tom Weaver, Michael Brunas, and John Brunas. McFarland, 2007.
