Develop the Tonal Range.
You have now established your light-
est light and your darkest dark. You
have also mapped out with lines the
shape of your main shadow area.
You are now ready to develop the
tonal range of your object in order to
achieve a three-dimensional object.
Make sure that you have a 4B pencil
and a kneaded eraser.
The light on the still life setup is hitting roughly the top quarter of the
vase. To achieve a lighter light area, you need to take an eraser and gently
erase the shape of the large lit area. Do not erase too much. This area
should not be lighter than the lightest light. You need to create a tone that
does not conflict with the lightest light. If you do not make this tone
slightly darker than the lightest light, the illusion of light, and therefore the
illusion of form, will be destroyed.
Erase and Add, Making Shapes
In this image, the artist is indicating the top lip of the vase. The artist
erased the shape that is catching the light. Again, do not make this area
lighter than the lightest light or highlight. Check your proportions, and
make sure the height of your object is proportional to its width. (See
“Measure Your Object” in Chapter 4.)