In this article I am going to take a deeper look at the effect of lighting in photography. If you have not already read the basic article on light, you can do so by clicking here. I will therefore assume that the reader is familiar with the concept of hard and soft light.
Natural vs Artificial Light
Lighting in photography can be split up into two broad types: natural and artificial. Natural light is basically daylight, while artificial light refers to any kind of manmade light source (e.g. candles, lamps, etc.).
Sometimes photographers can choose what kind of light they want to work with. A portrait photographer can decided whether or not to shoot the subject outdoors or next to a window, or to use some kind of lamp. However, other photographers may be forced to work with one or the other (e.g. landscape photographers are limited to using natural light).
Natural light is harder to control. It is affected by time of day, weather, season, etc. The light early in the day or just before dusk is softer to the light produced when the sun is high in the sky. Similarly, cloudy weather softens light as does pollution and fog.
Natural light is more unpredictable and can change rapidly. Cloud cover for example can vary in the degree to which it blocks or diffuses light. Similarly, lighting conditions change as the sun rises and falls.
Artificial light, on the other hand, is easier to control. The photographer can directly set up the angle, intensity, hardness, and distance of the light source. One thing to keep in mind is that different artificial light sources produce different colored light. This concept is discussed in greater detail in the following section.
Color of Light
Color sets the mood of your photograph and brings out the individual characteristics of your subject. Light is necessary for color, however different types of light will cast different colors, so it plays a very important role in how your final picture will look.
Varying levels of heat in different light sources produce different colored light. Often, our eyes do not perceive this color, but the camera records it as it is. For instance, normal tungsten light bulbs cast a yellowish-reddish light. Fluorescent light tends to cast a greenish light (which our eyes simply perceive as white). If you do not want these effects in your picture, you need to adjust the camera's white balance.
Adding some warm light, e.g. a little red or orange, to a photo will give the picture a "friendlier" or "cozier" feel. Using colors from the other end of the scale, such as blue and grey, will tend to make the picture less "lively". Each has its place depending on the desired effect.
Long before color photography started, painters used the yellow, orange, and red light from fireplaces to give the people they painted a warmer feel. Out in the nature you can use the colors of a sunrise or sunset to achieve the same warm look. However, this may not always be the effect you are after, so be sure to experiment with different kinds of light.
Although contrast is not always just about lighting in photography, I will include it in this section.
If the subject of your photo is "in contrast" to the rest of the picture they will stand out from the other elements in the scene, making them seem more dominant in the picture. If the difference in contrast is great, this is called "high contrast" while if the difference is small, it's called "low contrast".
There are two types of contrast. The first is where there is a significant light difference between the subject of the photo and the rest of the picture. This is called "tonal contrast".
For the most drastic tonal contrast, you can switch your camera to black and white mode - something which many artistic photographers use to great effect. Otherwise try composing your scene so that it has contrasting elements. You can do this by using different intensities of light, differences between the tone of the subject and the rest of the scene, and so on.
The other is called color contrast. To achieve color contrast, the photographer chooses the right colors for his subject and for the rest of the scene.
For color contrast, there are a number of things one can experiment with. For instance, warm and cold colors tend to contrast. Similarly, lighter colors tend to contrast with darker colors. Using fewer colors in the picture improves the effect of color contrast.
Both tonal contrast and color contrast can be adjusted in post processing, e.g. with a program like Photoshop or Gimp.
by Simon James Allanach, edited by Alan Frost
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