1. THE TRIANGLE PRINCIPLE
The Grammar of Film
THE TRIANGLE PRINCIPLE

2. Triangle Principle: Outline
Basic Concepts:
Linear Arrangements
Straight-line Composition
Right Angle Composition
Basic Body Positions
Lying Down
Kneeling
Sitting
Reclining
Standing
Line of Interest
Three Extreme Positions
Importance of the Heads
Five Basic Variations
External Reverse Angle
Internal Reverse Angle
Parallel Position
Right Angle Position
Common Visual Axis

3. Film Language: Visual Communication
Linear Arrangements are needed to relate the characters in a given scene with dialogue and action; there are two basic arrangements to achieve this relation.
A) Straight-Line Composition in which the two are on the same given line to the perspective of the camera.
B) Right Angle Composition puts one of the characters at a ninety-degree angle to the other - this is usually the character talking in the shot or take. A B

4. Film Language: Visual Communication
Straight-Line Composition
Right Angle Composition
Both linear arrangements form what is known as the “Line of Interest” in a dialogue.
The basis of the Line of Interest is the exchange of looks between the two characters: in the first clip from the film, The Bourne Identity, the characters are facing forward with their bodies, but looking at each other off and on as they talk; in the second clip from the film, Five Easy Pieces, the two main characters are at a right angle to each other, the one sitting forced to turn his head in order to converse with the other.

5. Film Language: Visual Communication
Basic Body Positions
The human body can assume one of the following positions; these positions can be taken by one or both of the characters in a dialogue scene.
Lying Down
stomach, back, side
Kneeling
erect or bent over
Sitting
on floor, on chair, on stool, on counter, etc.
Reclining
on back or on side
Standing
erect, hunched, relaxed, rigid, etc.
Basic Body Positions in Conversation
There are only four basic positions for conversation that work well on film.

6. Film Language: Visual Communication
Sitting with Opposing Glances in Straight-Line Composition
One sitting and one standing with Opposing Glances in Right Angle Composition
Both standing in Right Angle Composition
Both standing back to back in Straight-Line Composition.

7. Film Language: Visual Communication
Line of Interest
As previously discussed, two central characters will form a line of interest based on their exchanged looks.
Three Extreme Positions:
The line of interest can be recorded from three positions without having to cross that line.
Crossing the line can cause great confusion, so the general rule is to choose a side and stick with it.
Importance of the Heads:
Despite the fact that there are numerous ways in which to position bodies, what really counts is the positioning of the actors’ heads.
Even if one shoots the characters lying in bed back-to-back, a line of interest is automatic between their heads; so, take advantage of the fact that faces and eyes are far more important than bodies.

8. Film Language: Visual Communication
Triangle Principle: Three Extreme Positions
The placement of three cameras in a triangular relationship allows coverage of two characters with a line of interest between them.
Camera 1
shoots face of B and back of A.
Camera 2
shoots sides of A and B.
Camera 3
shoots face of A and back of B.
Line of Interest
in the triangle, line 1-3 is the common line of interest; it is re-inforced with shots from 2-1 and 2-3.

9. Film Language: Visual Communication
Importance of the Heads:
A line of interest always manifests itself between the heads of the characters in a given scene, so take advantage of this when selecting camera positions for shooting and editing.
Position 1
shoots face of B and back of A.
Position 2
shoots sides of A and B.
Position 3
shoots face of A and back of B.

10. Film Language: Visual Communication
Five Basic Variations:
There are three basic ways of covering a straight-line composition and two ways of covering a right angle composition.
External Reverse Angle
Two cameras parallel to the line of interest are directed in toward the two characters for opposing glances.
Internal Reverse Angle
Two cameras parallel to the line of interest are directed outward at each character for individual opposing glances.
Parallel Positioning
Two cameras parallel to the line of interest are shooting profiles of each character for opposing glances.
Right Angle Positioning
Two cameras are placed in complementary right angle to positioning of characters for opposing glances.
Common Visual Axis
One camera moves in on one character in a right angle positioning.

11. Film Language: Visual Communication
External Reverse Angle

12. Film Language: Visual Communication
Internal Reverse Angle

13. Film Language: Visual Communication
Parallel Positions

14. Film Language: Visual Communication
Combination of External, Internal, and Parallel

15. Film Language: Visual Communication
Right Angle Positions: Front

16. Film Language: Visual Communication
Right Angle Positions: Back

17. Film Language: Visual Communication
Common Visual Axis

18. The Grammar of Film
END OF LECTURE TWO