POI perception principle: The mind builds up its perception of an image from a series of rapid eye movements to the photograph’s points of interest.
Gestalt perception principle: The mind leaps to its perception of an image from a recognition of the individual elements in the photograph.
- Proximity: Visual elements in a photograph are grouped together in the mind according to how nearby they are to each other.
- Similarity: Visual elements in a photograph are grouped together in the mind according to their “sameness” to each other.
- Closure: Visual elements which are grouped together are seen to compose an outline shape.
- Simplicity (Occam’s razor): The mind tends to prefer simple visual explanations (symmetry, simple shapes, balance).
- Common Fate: Grouped elements with an implied motion are assumed to move together.
- Good Continuation: The mind tends to continue shapes and lines beyond the place where they end.
- Separation: The order for a figure in a photograph to be perceived, it must stand out from its background.
- Emergence: Parts of an image that do not contain enough information to explain them suddenly pop out as a result of looking long enough.
- Reification (fallacy): The mind fills in a shapre due to inadequate visual clues (see the Law of Closure above).
- Multistability: When their are insufficient or ambiguous perceptual clues, the mind tends to make elements of the image invert or “pop back and forth”. (For example, the alignment of Necker’s cube.)
- Invariance: (Less a principle than a property.) When objects can be recognized regardless of orientation, rotation, perspective, scale, lighting, or other factors, then the objects are said to be invariant.
Some basic graphical elements are more dynamic than others.
- Diagonals have more energy than horizonal or vertical lines.
- “Rhythm” (periodic patterns) create momentum and activity.
- Eccentric placement of objects induces tension.
Perspective and depth
- Linear perspective (this is what we usually think of as perspective in everyday conversation).
- Diminishing perspective (a special case of linear perspective where similar objects are getting smaller and smaller).
- Aerial perspective
- Tonal or color perspective (light or warm colors should be “close” and dark or cool colors in the distance).