Abstract
Considering the artistic presentation, we discuss two points in this paper. One is concenred with the modes of appearance of color, another with the contour effect. For our visual perception, the key modes may be surface color and film color. They are found not only in the outer world, but also within our visual process such as differentiates them. When we change the ways of looking at, these processes become clear, that is, brighter and clearer, or more cubic and three-dimensional than in the usual appearance. One of the examples is the so-called "Mach's card". In this case, we can perceive the shifting from a surface color perception to a film color perception, or vice versa. From such cases, we assume the existence of the two visual processes, one of which is the potential image forming process as a rather naive sensation, the other of which is the visual image forming process that enhances the figure character. Afterimage gives explicitly an example of both processes. The Hering's shadow demonstration tells us that the contour makes a surface color perception. Then we can suppose that the contour effect proves the linear drawing to be the expression gotten through the real nature in the visual perception.
