If the fade-out is used, it means three scenes instead of one, of course, because following the introduction of the "memory," or whatever it may be, you return to the scene proper, just as you go back to the wide-angle view after using a bust or a close-up scene. They would be numbered, for example, 17, 18 and 19, and you would write the action as follows:
17—Library, same as 6.
Fenton continues to make love to Beverly, presently ending what he is saying with an impassioned plea to fly with him at once. For just a moment she seems on the point of yielding; then she starts back and shows that she is thinking of what it would mean. (Fade out into—)
18—Bedroom, same as 8.
Dean, lying in bed, wakes up and calls out, as if calling to his wife. Then he falls back again on the pillow, exhausted. (Fade back to—)
19—Back to 17.
Fenton reaches out to grasp Beverly's hand, but she draws quickly back and urges him to stop pleading with her, at the same time crossing etc.
If you are using the "dissolve" or "interpose" (see definitions in [Chapter III]) you introduce the device in the same way as above; but bear in mind that the dissolve is somewhat harder to accomplish than the fade, and, again, while it merges one scene into another in an artistically beautiful manner, it is not so readily recognized by the spectator as an announcement, so to speak, of what is to follow.
The diaphragm (in or out), as the definition in [Chapter III] states, is used to indicate a lapse of time in the action of a story without using a leader. Also, in scenes between which there is supposed to be only a very brief interval, but which nevertheless call for a definite break of thought, the diaphragm is resorted to. Some directors will say "Circle out!" that being the effect on the screen—the oblong picture changing to a circle, which gradually becomes smaller and smaller until the diaphragm of the camera is entirely closed and the film "goes black." The reverse of this, of course, is called "diaphragming in."
As several critics have pointed out, the fade and the diaphragm should never be used to denote synchronized action. Action occurring in two places at practically the same moment should be cut one into the other, for this is the primary function of the cut-back. At no time should the diaphragm be used in this connection, either as a means of fading out or to reduce the field, for this robs the action of any suggestion of immediate change. Here the use of cutting back is imperative, and no other device should be substituted.