Quality

Light from a point light source such as an open flash or the sun is described as having a ‘hard quality’. The directional shadows created by this type of light are dark with well-defined edges. The shadows created by the sun are dark but not totally devoid of illumination. This illumination is provided by reflected skylight. The earth’s atmosphere scatters some of the shorter blue wavelengths of light and provides an umbrella of low-level light. Artificial point light sources create a much harsher light when used at night or away from the softening effects of skylight. The light from a point light source can also be diffused, spread or reflected off larger surface areas. Directional light maintains its ‘hard quality’ when reflected off a mirror surface but is scattered in different directions when reflected off a matte surface. This lowers the harshness of the light and the shadows now receive proportionally more light when compared to the highlights. The light is said to have a softer quality. The shadows are less dark (detail can be seen in them) and the edges are no longer clearly defined.

Harsh light Soft light - Orien Harvey

The smaller the light source, the harder the light appears. The larger the light source, the softer the light appears.

The control over quality of light is an essential skill when on location. Often the photographer will encounter scenes where the quality of the available light creates enormous difficulties for the latitude of the image sensor. The photographer must learn techniques to alter the quality of light or risk loss of detail and information. The quality of light, whether hard or soft, can be changed by diffusion and reflection.

A light source can be diffused by placing certain materials between the light source and the subject. This has the affect of diffusing and spreading the light over a greater area by artificially increasing the size of the source. Relative to its size, the further the diffusion material from the light source the larger the light appears to be. This softens the shadows, increases shadow detail and decreases the measured amount of light falling on the subject.

Reflection

Rodrick Bond

Light is reflected off surfaces to varying degrees. More light will be reflected off silver than off black. Reflection is a simple way of changing the quality of light. The amount of light reflected off a surface is directly related to subject contrast. A point source of light will give hard shadows to the left side of a subject when lit from the right. This is called high contrast as there are only highlights and shadows. A reflector used to reflect the light passing the subject back onto the left side would reduce the contrast by raising the detail in the shadows to a level closer to the highlights.

Activity 4

Illuminate a subject with a range of tones (another person) under many varied light sources. Include daylight, domestic lighting, street lighting, commercial and industrial lighting and light sources in your studio. Observe how the quality of the light varies from light source to light source and the differences in the reflective levels of elements in the photographs. Modify the quality of a light source by placing a diffusing material between the light source and the subject. Observe the differences in the highlights and shadows.