What is Direction?
The direction of your light source determines where the shadows will fall on both the subject and its surroundings. This in turn affects the appearance of texture and form. Since a light can be placed anywhere around your subject, particularly when you have free movement of a light source in the studio, there are infinite variations in the lighting direction you employ.
If you are using fixed, existing, light you may be able to move or rotate your subject instead, or perhaps plan out the right time of day to catch the direction of sunlight you need. The time of day can have an incredible impact on your photograph.
If you are imaging a landscape with rolling fields and hedgerows, a photograph taken during midday when the light is from above will produce a rather flat and potentially dull image as everything is bathed in the same light. The same scene shot earlier on in the day with the sun just rising or later in the day with the sun setting creates a more directed light producing highlights and shadows revealing the texture so that potentially every blade of grass could stand out.
We tend to accept lighting as most natural when directed from somewhere above, mimicking the sun; after all, this is usually the situation in daylight. Lighting a subject from below tends to give a macabre, dramatic, even menacing effect. Compare (C) with (H) in Figure 7.4. Frontal light from next to the camera (G) illuminates’ detail, gives small shadows, minimizes texture and flattens form. Reflective surfaces seen flat on flare light straight back towards the lens. This effect can also be seen when you use direct flash from the camera.