An eyeline match is a technique used in film editing, which relates the scenic space across two shots. The first shot shows a person looking towards an offscreen object. There is a cut to the second shot, which shows the object of the person's gaze and the space surrounding the object. Neither the first shot nor the second shot contain both the observer and the object. "Eyeline" refers to the line traced from the eye of the person in the first shot to the object in the second shot.

Typically, eyeline matches preserve spatial continuity by respecting the axis of action. That is, if the person in the first shot was presented on the left side of the screen and was looking right, then the object in the second shot appears on the right hand side of the screen. Commonly, an establishing shot, displaying the space around both observer and the object, is shown first to clarify the situation.

However, eyeline matches "work" even without an establishing shot. When film viewers are shown a person looking offscreen followed by another shot, they tend to interpret the sequence as the person from the first shot looking at the object in the second shot, as if the person and the object are in the same space. This is explained by the Kuleshov effect, named after 1920s Soviet filmmaker Lev Kuleshov. Briefly, the Kuleshov effect occurs when a series of shots shown without an establishing shot causes viewers to believe that the events in each shot are all in the same space.

A diagram may be useful at this point (I apologize in advance for the crude ASCII artwork):

+------------------------------------+
|                                    |
|                                    |
|                                    |
|                                    |
|    O                       O       |
|   / \                     / \      |
|   |A|                     |B|      |
|   | |                     | |      |
+------------------------------------+

Shot 1: The establishing shot shows both the observer (in this case, person A) and the object (person B), as well as the space around them.


+------------------------------------+
|                                    |
|      ___                           |
|     /   \                          |
|     | o o ---eyeline--->           |
|     @  \|                          |
|     \__-/                          |
|    /     \                         |
|    |  A   \                        |
+------------------------------------+

Shot 2: The first shot of the eyeline match, showing a medium shot of the observer (person A) looking offscreen. Note that in both the establishing shot and this shot, person A is on the left side of the screen.


+------------------------------------+
|                                    |
|                       ___          |
|                      /   \         |
| ---eyeline--->       |o o|         |
|                      | v |         |
|                      \_-_/         |
|                     /     \        |
|                    /   B   \       |
+------------------------------------+

Shot 3: The second shot of the eyeline match, showing a medium shot of the object (person B). In both the establishing shot and this shot, person B is on the right side of the screen.


(In shot 3, we see person B straight on. If we (or the camera) were in position that person A is in, we should see person B at an angle. This sort of eyeline match is known as point of view cutting.)

Shot/reverse-shot sequences, which are a very common way to film dialogue between two people, often employ eyeline matches when only one person is shown in the frame, such as the sequence illustrated above. Not every shot/reverse-shot sequence employs eyeline matches; for example, the two people may not be facing each other.

Let's use a scene from Fight Club, Everything2's favorite film, as a concrete example of an eyeline match, used with a typical shot/reverse-shot pattern. Warning: Very minor spoiler ahead.

Around five minutes into the film, the Narrator (Edward Norton) is talking to a doctor (Richmond Arquette) about his insomnia. The scene opens without an establishing shot, showing the doctor in a three-quarters view, medium shot, slightly on the left side of the screen, looking offscreen to the right; this is like Shot 2 in the diagram above. There is a cut to a shot of the Narrator, who is looking straight out of the screen; this is like Shot 3 in the diagram. From the eyeline match in these two shots, we infer that the doctor and Narrator are talking to each other in the same room. The film then alternates shots of the doctor and the Narrator as they speak. Finally, there is an establishing shot (really, a reestablishing shot) of both characters together in the frame, confirming our interpretation that both of them were in the same room.

Eyeline matches are a powerful editing technique used to clarify spatial relationships in films, used in virtually every film because they are simple and intuitive. They are so effective that spectators rarely notice them in action.


Notes

David Bordwell and Kristin Thompson. Film Art: An Introduction, Sixth Edition. (New York: McGraw-Hill, 2001).


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