the two different characters.  But it is a much easier matter for the dual-role actor, made up as Carton, to be photographed singly in one part of the room as he goes through with the action of one or more scenes, after which, dressed as Darnley, he goes through the synchronized action of that character.  Synchronization—­or harmony of movement in time—­of course demands that the action of both characters be properly matched—­to use a common and easily understood term—­but it will be seen that when the spectator watches only one character at a time there is not the need for the perfect synchronization of action that is always demanded of the wide-angle double-exposure scene, in which one man, playing two different characters, must face himself and keep the action natural and convincing at all times.

Very few things in the development of motion picture art have advanced so noticeably as this trick of portraying dual characters on the screen by means of double exposure of the film.  Theoretically, it is extremely simple.  There is a middle—­or at any rate an arbitrary—­dividing line to the stage.  A mask being placed over one-half of the camera lens, the film is run through and the action of Carton in a certain scene in which he is supposed to face Darnley is taken.  Careful track is kept of just what important moves he makes at different stages of the count.  Later, after he is made up as Darnley, the first half of the lens is masked in the same way as before, while the second half is exposed and the action of Darnley is gone through with, with the gestures and other action properly timed to synchronize with the action of his “double”—­and that is all there is to do.  But the skill of the director is tested in his timing of the moves of the characters, just as his knowledge of lighting and backgrounds is tested so as to avoid showing the line where the two differently exposed parts of the film join.  Then, too, certain directors have, of late, procured some “double” effects which well deserve to be called wonderful, as when in a certain William Fox film the two different characters, played by the one woman, are made to meet and kiss each other most naturally.

To repeat, double exposure (to use the simplest term for this camera trick) has made possible the writing of many stories for the screen which a few years ago would have been rejected because of the inability of the company to procure two people similar enough in appearance successfully to portray the “doubles.”  No author with a really fine idea for a dual-character story need hesitate to offer it to the film companies today.  But there is still enough additional trouble attached to the production of this kind of story to justify the editors in rejecting everything but the very best in the way of plots.

16.  Features