Principles of cinematography : a handbook of motion picture technology (1953)

16-MM CAMERAS AND ACCESSORIES 363 the appropriate length of film, inserting the second title and rotating the shutter until edge 'D' occupies the position to which edge *F' was first located, correspondingly increasing areas of successive frames may be revealed until the new title is fully shown across the entire frame area. Single frame exposure should then be continued throughout the entire length of the shots although animation may not be taking place. This is necessary since a change in exposure will occur if the camera is run continuously once the wipe has been completed. Although many manufacturers recommend that the lens aperture should be opened by one 'stop' when changing from single frame to continuous exposure, such an adjustment will not entirely compensate for such changes and may produce variations in image density in the final pictures. CINE CAMERA Fig. 157. — Set-up for titles with moving background by "single-shot" exposure. Titles with Moving Backgrounds By using a 'still' picture camera in front of the cine camera it is possible to photograph titles which have moving backgrounds which, unlike those produced by other processes, are as sharply focused as the titles themselves. The arrangement for this type of work is shown in Figure 157. Both the still and the cine cameras should be mounted upon a base board which may then be attached to a tripod head. The still camera must be of the type which uses plates or cut films and which has a ground glass focusing screen. The still camera is then trained upon the background scene and, with the ground glass in position, this scene is sharply focused in the plane which is normally occupied by the plates or film. The titles consisting of black letters written on clear celluloid are then inserted in the runners at the back of the camera. The