1. Atmospheric Perspective creates the illusion of space by diminishing values, colors and details as objects move back in space.
2. The location of objects will identify their location within a composition. Objects higher on the picture plane will a appear farther away whereas objects lower on the picture plane will appear closer to the viewer.
3. Diagonals will also suggest depth due to the fact that one end of the line whether actual or implied is higher on the picture plane and the other is lower. An implied diagonal is one suggested between the relationship of two or more objects. The open cylinder in the drawing above has a diagonal movement towards the cylinder in the upper left corner.
4. The proportions of similarly sized objects will diminish as they move back in space. Notice how the objects in the drawing above become smaller the closer they get to the horizon line.
5. Dark values are likely to recede whereas light values will advance.
6. Overlapping forms will suggest depth by establishing foreground and background.