The aim of this initial exercise was to create a range of tones from white through grey to black. After several attempts I had a sequence that showed a clear tonal progession.
The next step was to find the tone that was midway between white and black and apply that tone to two small scraps of paper. These were placed at either end of the scale so that the same tone of grey was sitting beside white at one end and black at the other.
When placed next to white the grey appears to be lighter in colour – against the black it appears darker.