الكروما .. كتاب التصوير الملون ، الكاتب عبد الفتاح رياض

Chroma: Chroma

If we say that the origin of the hue indicates its type, essence, or flavor (for example, red or green, etc.), then its value indicates the degree of its brightness.

As for chroma, it is the adjective that indicates the extent of color purity, i.e. the degree of its saturation, and thus indicates the extent of its mixing with neutral colors (white, gray or black).

We have already mentioned that the origin of the hue color is shown in a circular way (Fig. .

The closer the color is to the axis, the more it indicates a lack of saturation, i.e. mixing it with a neutral color. If the color is close to the axis and in the alignment of the lower values, which tend to be blackish or dark gray, then this indicates that the color has decreased its saturation, i.e. the degree of chroma has decreased in it as a result of its increased mixing with a dark gray or black color (Fig. 30).

We also infer from the proximity of the color to the axis and the alignment of the higher values, that the color has decreased its saturation as a result of its increased mixing with white or light gray (Fig. 30).

Chroma degrees of red

Chroma grades for the purest green

Perfect white is light red - mixed with a very light shad

Chroma gradations start from the number (0), which indicates gray neutral colors, and the gradations may reach 16 degrees or less than that sometimes, as the colors do not reach their maximum saturation after equal degrees, for example: red reaches its maximum saturation and purity after 14 chroma degrees, This is if the value degrees = 4 or 5, while the blue-green (opposite to red in the circle of color origins) reaches its maximum saturation after only 6 chroma degrees. Yellow reaches its maximum saturation after 12 chroma degrees in front of value No. 8, and reaches 16 chroma degrees in front of value No. 8. Thus, we find that the degrees of chroma differ according to the origins of the colors, Hues, and according to their values. The table shown in Figure 31 explains the above. It is not usual to indicate the degree of chroma in front of the value number 1, because the value of the darkest color origins is lighter than black and gray.

Whenever the color is farther from the axis, this indicates an increase in its saturation, even if it reaches the tip of the chroma gradient. This indicates that the color has become pure, not mixed at all with any neutral color, and that it has reached its maximum saturation.

It is very dark ( whose value = 1 ), and it is also not usual to show

chroma degree in front of the value; Because the lighter colors are made up of the darker

White (whose value = 9).