Value Study - Three Tonality System

3 Tonality System: A minimum of 3 tones is required to create the illusion of 3D shapes on a flat surface. White, mid tone and black.

Objective: (1) Create a value scale that demonstrates five variations of tonality.  Starting with white and gradually transitioning to black. (2) Draw a sphere, visualize a light source and render tonality so as to make the sphere appear to be 3-d.

Directions: (1) Using a ruler, create a row of 5 boxes.  Render each box so as to create a value scale.  Starting with pure white and gradually transitioning to pure black. (2) Draw a sphere and a imaginary light source.  Visualize how the light strikes the sphere and apply a minimum of three tones so as to render the sphere in 3D. Apply a cast shadow to the sphere.  If you have extra time consider the background.  Apply shading to surrounding areas.

Rubrics:

1. Demonstrates a minimum of three tones: white, mid & dark
   
2. Evidence of layers of tonality overlapping, creating gradual transitions of tonality from pure white to pure black
   
3. Final product displays contrast and creates the illusion of 3D form(s) on a flat surface
   
4. Evidence of craft.  Each line drawn should carry the same weight of importance.  Overall quality of line application should be consistent.