from the ASC Manual October 1935
by
Jerome H. Ash, A.S.C.
WOULD you like to make lap-dissolves without rewinding—to dissolve backgrounds without changing the foreground—to make ‘arty’ titles with moving cloud backgrounds, in which the clouds blow into words—to make a single actor play bridge with himself, or even multiply into an army—all at a single ‘take’, with any 16mm, or even 8mm camera?
Don’t say such things can’t be done. They can be— with mirrors!
But before we get too deeply into these tricks, let’s clear up the fundamental matter of focus; if we don’t, it will surely trip us up later. Looking at a mirror, one would naturally figure that the mirror itself was the thing to focus on—but it isn’t: if we want a sharp picture, we must set our focus for the combined distances from lens to mirror AND from mirror to object. For instance, if we want to make a shot of a girl sitting at a dressing-table, showing both the girl and her reflection in the mirror, here’s the way to go about it: first, shoot from an angle, so that the camera won’t be reflected into the picture.
Next, suppose the girl is, say, two feet from the glass, which, in turn, is eight feet away from the lens. The correct focus will be eight feet plus two feet, or ten feet.
One of the simplest mirror tricks is done with two unframed mirrors, set at an angle of about 75° to each other, and with their inner edges touching. The subject takes his place between the mirrors, with his back to the camera, which is carefully screened behind a curtain. How many images you get will depend upon the width of the mirrors: with wide ones, you can get five different angles on your subject—the direct back view, and reflected profiles and three-quarter front views from either side. The vital part of the trick—as in all mirror trickery—is to keep the camera’s view confined to the mirrors: if you shoot beyond their edges, you simply give away the trick. If you can get full-length mirrors, incidentally, you can make very interesting full-figure shots this way.
Next comes the trick of multiplying one person or object infinitely by the use of two mirrors parallel to each other. You put your subject between the mirrors, and aim the camera toward it, just clearing the edge of the nearer mirror. If you line things up properly, you’ll get first the direct view of the object itself; just beyond it, the reflection in the farther mirror; next, the re-reflection of the nearer image, followed by the re-reflection of the first image, multiplying and re-multiplying till Gertrude Stein and Einstein couldn’t figure it out. Naturally, with the size of mirror that most of us have available, miniatures and close-ups are about the limit; but if bigger mirrors are available, full-length shots are just as easy to make. It is important, of course, to make sure none of your lights reflect directly into the mirrors.
The other day, William Stull, A.S.C., told me of a time when, on location several hundred miles from Hollywood, he ruined his last filter just when he had to get a heavily-corrected filter-shot of some clouds. Remembering his high-school lessons in polarized light, he made the shot by photographing the reflection of the scene in a black mirror—which gave him a black sky against which the clouds stood out beautifully.
But here’s an even simpler way to get filtered cloudeffects for title-backgrounds. You don’t even have to have any clouds! Figure 1 shows the set-up. You place an ordinary mirror flat on top of a table, and above it slant B, a piece of glass, which carries your lettering. The camera is at C, shooting down onto the glass. On the other side, at D, is a strong light—preferably a spotlight—which is focused on the mirror. The space between the camera and the opal glass should be kept as dark as possible. On top of the mirror sprinkle a fine layer of sand, brushed thin with a tuft of cotton. When you are ready to shoot, blow a stream of air over the mirror (a small electric fan will often do nicely).
As the sand skitters across the mirror, it blocks out the reflected light, and you get the effect of clouds against a dark sky. If you are shooting reversal film, the sand will represent the dark sky; if you are shooting negative (intending to use the negative for your title), the sand will represent the clouds. You can also get interesting effects of this type by using iron-filings, which you ‘blow’ by moving a magnet under the mirror.
Now, if you want the clouds to shape themselves into words, use a plain opal glass in the inclined frame, and trace your letters on the mirror with paste or mucilage.
When you sprinkle on the sand, that that falls on the glue will stay put, while the rest will be free to blow away. Making the shot as a negative, you’ll have clouds that blow around and finally shape themselves into the title. A slight degree of slow-motion often helps this sort of a shot, by the way.
This next trick calls for quite a bit of construction but it is well worth it, for you can do no end of tricks with the device, once you have it made. You begin by making a shadow-box as shown in Figure 2. The three openings at “A“, “D” and “E” must all be the same size.
At “B” you place a sheet of plate-glass in the shadowbox, at an angle of 45° to the camera (“C“) : and openings “D” and “E” must be the same distance from the glass.
In use, you place whatever foreground subject you wish at “A“, and two different backgrounds at “D” and “E“.
Let’s say we begin our shot with background “D” in use: the lights illuminating it are on, while those at “E” are off. When we want to fade our backgrounds, we dim the lights at “D“, and slowly turn those at “E” on. The subject, at “A” is constantly illuminated, and moving normally.
The result is that our scene begins quite normally, with the subject moving against background “D“, and—without any change in the foreground action—the background suddenly lap-dissolves into an entirely different view !
The only limiting factor to this trick is the size of the pane of plate-glass “B“, which reflects the scene at “E“.
Made on a small scale, the shadow-box doesn’t cost much; and even with a fairly large pane of glass the cost will be reasonably low, for you can make the shadow-box cheaply out of a lath framework and black muslin.
The simplest way to lap-dissolve your background-lights is by using a water rheostat, which you can make for a dollar or so. You simply fill two gallon crocks with salt water, and hang a piece of insulated wire soldered to a metal weight in each crock. These should extend all the way to the bottoms of the crocks, and both are connected to one side of the electrical circuit. Next, you make a simple wooden framework above the crocks, with a couple of pulleys, over which you string two other weighted wires, connected to the other side of the circuit. These last two electrodes are arranged so that when one drops to the bottom of its crock the other is pulled out of its jar. Thus, the current is evenly switched from one circuit to the other, lap-dissolving the lights.
If you make this shadow-box set-up on a small scale, you can very easily make all sorts of lap-dissolves to cut into any of your films, regardless of when the films were actually shot. Simply enlarge one frame of the end of Scene A, end one frame of the beginning of Scene B, and place the enlargements at the two ends of the shadow-box.
Make your lap-dissolve while rephotographmg the enlargements, cut the lap into place between the two scenes—and there you are! Naturally, it will work just as well fading from a title to a scene, or a scene to a title, as it will fading from scene to scene. And it will enable you to use the first frame of any scene as a background for a title, with the title fading out, and the scene starting to move.
If you make your shadow-box big enough for full-size trick-shots, you can not only fade from one background to another, but you can create ghosts or spirits without resorting to double-exposures. In this case, the two backgrounds are identical—and they must be set up very carefully so that both the direct view and the reflected view coincide exactly on the film. Now, if you have your “ghost” in one end of the shadow-box, your “dissolve” will simply fade him in, without making the slightest change in either the foreground or the background. If you place a piece of furniture at “F“, to conceal the ghost, so his image won’t grow larger as he comes close to the glass, you can have him walk right out of the reflected scene into the foreground.