If you've spent any amount of time listening to art teachers, you've probably heard the saying
"It's all about value." And I cringe every time I hear it because it's often used without context. Is value important? Of course, but the issue is much more complex. If a painting is based on value as the prime directive then color is subject to the value choices. However, if a painting has color as the primary directive then values are selected for the color. Take, for example, the above Monet painting (pardon the poor imagery). The color version is the original. If by simply removing the color from that painting we are left with the image at top left. There are obviously different values but the overall effect is lacking as a B/W picture compared to the original . To remedy this we have to adjust the values to make for better contrast and effect . The result is the bottom left picture. Now, look back at the color version and you will probably notice that it feels as if it is actually more like the bottom black/white picture in terms of contrast (especially with the original). Why? Because Monet made color the prime directive in this picture and the values are incidental to the color choices.
This is just to show that while value is clearly important (especially in drawing) it's not always the one pulling the reins...
