Table 1.
Description of the seven global properties of natural scenes used in Experiments 1,2 and 3
| Structural properties |
|---|
| Openness [1,2,3,4] represents the magnitude of spatial enclosure. At one pole, there is a clear horizon and no occluders. At the other pole, the scene is enclosed and bound by surfaces, textures and objects. Openness decreases when the number of boundary elements increases |
| Expansion [1] refers to the degree of linear perspective in the scene. It ranges from a flat view on a surface to an environment with strong parallel lines converging on a vanishing point |
| Mean depth [1,3] corresponds to the scale or size of the space, ranging from a close-up view on single surfaces or object to panoramic scenes |
| Constancy properties |
| Temperature [2,4] refers to the physical temperature of the environment if the observer was immersed in the scene. In orther words, it refers to how hot or cold an observer would feel inside the depicted place. |
| Temperature [4,5,7] refers to the rate at which the environment depicted in the image is changing. This can be related to physical movement, such as running water or rustling leaves. It can also refer to the transience of the scene itself (fog is lifing, sun is setting). At one extreme, the scent identify is changing only in geological time, and at the other, the identity depends on the photograph being taken at the exact moment. |
| Functional properties |
| Concealment [4,6] refers to how efficiently and completely a human would be able to hide in a space, or the probability of hidden elements in the scene that would be difficult to search for. It ranges from complete exposures in a sparse space to complete concealment due to dense and variable surfaces and objects. |
| Navigability [2,4,5] corresponds to the ease of self-propelled movement through the scene. This ranges from complete impenetrability of the space due to clutter, obstacles or treacherous conditions to free movement in any direction without obstacle. |