In the diagram below, both lights are the same size, but the bottom light is positioned at about three times the distance. Again I have placed vector lines at three points along the light source to represent rays of light at the points that just touches the model's face. What becomes obvious when looking at these lines is that the angle of the lines is greatly affected by distance. When the light is close, the angle is greater than when the light is farther away. In this case the close light has about 55 degrees of spread from the light rays emanating from the extreme edges of the light source. The light that is farther away has about 12 degrees of spread from those same two edges of the light source.
This concludes the discussion for the quality of light. Next post we will delve into discourse on light temperature, which will be the last section for this series.