Abstract

Tone or value refers to the measurement of the relative darkness or lightness in visual art. It is based on Ross’ definition with a scale from 1 to 9, with 1 as the lightest and 9 as the darkest; whereas, the Munsell scale is reversed and uses a scale of 0 to 10. Various art forms including drawing, painting, photography and design, often regard tone as a very important visual element. For art forms such as drawing and painting, the training generally depends on perceptual exercises, such as still-life drawing or outdoor painting exercises. Fine artists often develop their own preferences for various tonal designs depending on their working environment, location, or their travel experiences elsewhere. Various lighting conditions related to basic tonal arrangements or color moods are often discussed briefly in art training books. However, there is no concrete framework to discuss how different weathers or moods can be designed based on tonal arrangements. In photography, the discussions are focused on various lighting conditions and how the equipment can be professionally fine-tuned to arrive at a desired mood. Light histograms are used to measure light so as to understand various lighting conditions and moods. In design, the importance of tone was briefly discussed as one of the three attributes of color. Masterpieces from different periods were introduced by the author to discuss the pattern of tones. Tonal design was introduced brusquely as “key” (relative lightness of an image), where “low-key images” referred to darker images and “high-key images” referred to brighter images. Drury and Stryker comprehensively discussed the various relationships of tone and image design in drawing. Tone was discussed in relation to the constructions of forms, the illusion of space and atmospheric perspective. Tone range was briefly discussed in conjunction with tonal design by Drury and Stryker in 2009. In order to further extend the tonal design concept, this article uses basic mathematical graphic models as reference to simplify the teaching and learning of the concept. With the use of basic parameters and simple mathematical charts as visual aid, students will gain an understanding of what governs the basis of tonal design.