ENGINEERING SPECIAL EFFECTS. There are many techniques used in special effects. Start of film techniques in the 1920's until now rapidly adopted CGI (Computer Generated Imagery).
The use of special effects techniques are not limited to just one in filmmaking. Commonplace, if a film uses various combinations of special effects techniques.
Traditionally, special effects can be divided into two, namely Optical Effects and Mechanical Effects (or often called In-Camera Effects).
The difference is that at the time of its use. Optical Effects refers to the manipulation of the image after shooting is completed. While the Mechanical Effects refers more to the use of special effects when shooting.
Mechanical Effects was the first time emerged, namely the use of miniatures, rear projection, pyrotechnics, stopmotion animation and matte paintings. Optical effects appear then use the bluescreen, compositing, multiple exposures complement the special effects techniques in the early era of its development.
Then digital compositing, animatronics, prosthetic makeup, and computer-generated imagery (CGI) as a complement of modern techniques in the world of special effects.