Notes on Special Effects (Sp-EFX, or Simply F/X, although F/X can refer as well to sound along with visual special effects)

Bob Nowlan

A.

=    Any image or element within an image obtained by conventionally unusual, or extraordinary, technical means (often, as well, what seems to run sharply counter to the temporal and spatial relations that are conceivably possible using the unaided human eye–or ear).  


    Traditionally achieved either through a.) special photographic processes–i.e., what are called visual or photographic special effects (including optical printing processes)–or b.) created before the camera when camera is shooting normally–i.e., mechanical special effects (e.g., creation of rain, snow, fog, fire, and explosions; use of models and miniatures; use of elaborate make-up; use centrifuge or wires to give impression of weightlessness).    Now most often used to refer to photographic processes (and, of late, computer-generated processes).


    Important to note well, however, that film makers have made use of special effects since virtually the beginning of the initial practice of film making, and, as such, computer-generated special effects are only a quite recent phenomenon.  What’s more, computer-generated special effects are not necessarily always by any means qualitatively “better” than the many creative achievements of special effects film makers prior to this point in time.  In fact, many of these previous special effects technicians and artists had to show greater creativity and demonstrate more talent than those who rely strictly upon the most advanced kinds of current technologies.


B.

    Here’s some historic clusters of kinds of (Visual) F/X techniques:

1.     Stopping the camera and replacing the object before the camera, or altering the object before the camera, before the camera is then turned back on.  This refers, of course, to stop-motion cinematography, broadly conceived, including time-lapse cinematography.

2.     Double or multiple exposures.   Also, other severe distortion or altering of image appearance through direct manipulation of the camera (such as strobing).

3.     Miniature shots (shots of miniatures made to look life-size).  Models (life-size stand-ins or close-size stand-ins for real objects) .   Animatronics/puppetry.

4.     Composite printing: combining shots; superimposition; split screen images.  Insertion of animation into live-action film prints.   Drawing, scratching, coloring, dyeing of frames (before or after shooting).

5.     Matting/Matte shots (actual set and painted scene are combined by re-exposing the film twice with mattes blocking out the appropriate areas of the negative from the first exposure).  Glass shots (shooting through glass).  Traveling mattes (where the matte changes from frame to frame, allowing moving subjects to be combined with separately photographed backgrounds); these are often combined with recording of subjects acting in front of black, white, blue, or green screens.  

6.     Use of dissolves, fades, wipes (achieved both within the camera, and, especially, in the processes of printing and editing).


7.     Slow and fast motion.  Ramping.  Skip-frame printing, multiple-frame printing, and freeze-framing.

8.     Rear projection, front projection, and mirror shots.   Aerial-image photography combined with mirrors to create composite of image from the air with image from the ground.

9.     Use of extreme (wide-angle or telephoto) lenses to elongate, compress, or otherwise fragmentize/distort the picture.

10.     Streak-photography or wet-photography; precise, and especially automated, camera motion-control devices, including ‘go-control’ that precisely, and automatically, regulates the use of camera shutter and shutter speed, the opening and closing as well as the size of the opening and closing of the aperture, and the movement of the camera on/with the camera apparatus.

11.     Computer graphics and animation.  CGI; morphing.

12.     Virtual dolly; bullet time.

C.

Some Key Ones, More Precise (Yet Simple) Definitions:

1.     Slow-Motion: projecting at speed slower than recording (shooting) speed.

2.     Fast-Motion: projecting at speed faster than recording (shooting) speed.

3.     Ramping: shifting speed of motion within the shot, usually by slowing down or speeding up the rate at which the scene is shot in terms of  number of frames recorded per second (which are then subsequently projected at a constant rate).

4.     Freeze-Frames: repeatedly printing the same recorded frame so that it appears to linger longer, to freeze in time, as it is projected.

5.     Stop-Motion: constant, or frequently recurrent, starting and stopping of the camera while the object being recorded is changed in between the time the camera is turned off and on again.

6.     Time-Lapse: stop motion involving the shooting a single frame at a time with a lengthy duration between each shot to show some process that takes place over a long period of time and yet when printed and projected using this technique seems to happen quite rapidly.

7.     Pixillation (with film cameras, not the same as with digital video cameras): stop-motion involving the slight movement of characters, or other subjects, from the time the camera is turned off to the time it is turned on again, with this process repeated a significant number of times to achieve the effect when printed and projected subsequently.

8.     Double and Multiple Exposures: superimposition of two or more images, one over the other, by exposing the same piece of film two, or more times.  Often used to create the semblance of a person remembering, thinking, or dreaming; ghosts or other supernatural effects; commentary on the scene by emphasizing a striking visual contrast with(in) the scene; and to suggest a change in time–and place–with movement toward dissolving from one scene to another.   Not as commonly used today.

9.     Strobing: a seemingly disconnected and jerky effect between images of the same object on the screen.  Often achieved by panning a static scene unusually fast, or by having a subject move unusually fast in front of a static camera.

10.     Models and Miniatures: creations of artificial stand-ins for ‘real’ objects  or other entities which are filmed as if ‘real’ and not ‘artificial’; miniatures of course being small models of much larger objects or other entities.  Can include use of animatronic devices (operated by computers or remote control) and traditional (non-animatronic) dolls/puppets.

11.     Rear and Front Projection: rear projection involves the projection of either a still or moving picture onto a translucent screen in front of which live action is photographed so that both the background on the screen and the foreground action are combined into a single image on the exposed film.  Front projection projects the background still or moving image from the front, rather than from the back, such that the projector, placed in front and to the side of the camera at a 90-degree angle, projects the background onto a semitransparent and semireflecting mirror placed at a 45-degree angle to both the projector and the camera; the mirror reflects the image onto a special reflex screen made of tiny glass beads that reflect back to the camera almost all of the light rays from the projected and recorded scenes; and the camera shoots the scene (as well as records the reflected projection) through the mirror.  

12.     Matte Shots and Traveling Matte Shots: a matte shot results from the combination of parts of two or more separate images by means of mattes (often, in simplest form, comprised of a special kind of thick black-i.e., highly opaque-tape) for blocking out unwanted areas and protecting previously exposed areas during photography or printing; it can also refer to any shot in which part of the scene is matted out so that the photographed area can be joined with part of another image subsequently for a composite picture.  In traveling matte shots, the mattes change shape from frame to frame allowing moving action to be     combined with other picture elements in a sequence of composite shots.  

13.     Blue and Green Screen Processes: actors act in front of a blue or green  screen which is then replaced with a separately recorded background image to replace the blue or green screen.

14.    Split Screens: a visual composition in which the frame is divided into two or more separate images not superimposed over each other.  Achieved by first matting one portion of the film in the process of development, and then photographing into the matted side of the film another image while the previously photographed portion is this time protected by another matte.

15.     Superimpositions: placing two or more images on top of each other within a single frame (or across a series of consecutive frames).  Can be achieved by reexposing the same piece of film, yet normally achieved during optical printing process where separate images are printed on top of each other.

15.     Glass Shots, Mirror Shots: glass shots involve shooting through glass  on which is painted a portion of a scene to be added to the recorded image (and, alternately, previously shot photographs can be attached to the glass and added to the recorded image together with the scene of action).  Mirror shots are any kind of shot that uses a mirror, or  multiple mirrors, to achieve a special effect: placed in front of and below or above the camera (lens), or placed strategically on the set in  relation to the position of the camera versus the scene of the action, to create reflections.  

15.     Virtual Dolly, Bullet Time: simply put, arranging a string of stop-motion cameras around a scene or a part of a scene, which are automatically turned on and off in sequence, and which can convey the illusion of a super-fast camera movement (a dollying) around the scene when printed, edited, and projected.
 
15.     CGI, Morphing: simply put, computer-generated imagery of diverse kinds, and the transformation of a computer-generated object or entity into a qualitatively different-appearing object or entity within the single  shot.