Contrast is the difference between values that sit side by side. High contrast puts very light next to very dark. Low contrast keeps the values close together.
Key describes the overall value of a picture. A high-key picture is mostly light values, like a foggy morning. A low-key picture is mostly dark values, like a night scene.
Key idea
High contrast: very light beside very dark. High key: mostly light values. Low key: mostly dark values. Most strong drawings use the full range somewhere.
Why it works
The eye goes first to the place of highest contrast, so artists put their strongest light-against-dark where they want you to look. Key sets the mood: high key feels airy and gentle; low key feels quiet, dramatic or mysterious. Painters call strong light and dark modeling chiaroscuro, Italian for "light-dark."
Worked example: A foggy morning
You want a drawing of a foggy morning. What key and contrast fit best?
- Fog makes everything pale.
- It also softens the differences between values.
Answer: A high key with low contrast.
Common mistake
People stay in the safe middle grays, so the drawing looks washed out. Use the full range somewhere: the white of the paper for the brightest light and your darkest dark for the deepest shadow. Squint to check that both are there.