Using Space Management and Layering, we manipulate the two dimensional photographic space and introduce depth by changing the relationship of distance between elements and their size.
Positive and negative space occupies all areas within any scene in the camera's viewfinder. Positive space is simply, the space the elements or subjects occupy within the frame; Main subjects is the positive space that visually is the most important element in the frame and Secondary Subjects are all other positive spaces.
Negative space is all the other areas around the positive spaces. The positive and negative spaces are both considered layers. The way that we create and arrange these spaces is the concept of layering. The alternation of space layers is creating depth in the image. Not all photographs will contain many positive/negative spaces and layers. Some very successful photographs only contain two layers, although more depth is perceived, when we allow more layers in a composition.
These examples illustrate the concept of layering. Let's begin by discussing the positive spaces in the first image, early morning shot the ducks in the lake. The ducks are positive spaces and the blue water is negative space.
In the second image the birds are positive spaces, lets add the stones also. The distant bush and the dark water are negative space.
The perceptions of depth will be more profound if a cohesive negative space layer separates any two positive space layers. The more negative space we allow, the more defined, the positive space will become. The visual movement between them and through the negative space layer will be fluid and uninterrupted. If two positive spaces merge, a visual distraction will take place. The comprehension of the space relationships becomes even more disruptive, when the two merging positive spaces exhibit similar visual characteristics in tone, color, shape and or texture. The extent of a distraction depends on how similar the two spaces are in these characteristics. If the two spaces are exactly alike, they visually become one space and there will be no perception of depth between the spaces.
These two images will clarify my point. In the first image the depth is less due to merging of two similar postive spaces and the depth is increased in the sencond one we due to introduction of negative space in between those zebras.