Types of Light
Before we start trying to use the light, we should take a look at the various types of light that you will deal with when making images. Knowing the type of light will help you control your white balance, but it will also give you an indication of the quality of the light.
Because the sun passes through the Earth's atmosphere, you will find that daylight can be one of the most varied light sources you ever encounter. It can range in color temperature and intensity based on several factors. First off, there is the time of day that you are taking the photos; the color of light is very different at sunrise than it is at mid-day. There is also a difference in the intensity of the light. Mid-day sun can be very harsh, creating hard-edged shadows (Figure 4.1). The shadows that occur after sunrise and before sunset are usually longer and add more definition, especially to a landscape (Figure 4.2).
Figure 4.1 The mid-day sun can be some of the harshest and most direct light to shoot in, but sometimes it is your only option.
Figure 4.2 Sunrise, with the light coming in low from the horizon, provides some beautiful light across the landscape.
This can also lead to extreme exposure variances between light and dark areas. This is known as contrast. Having a lot of contrast means that you will often have to compromise your exposure in some way or another. If you shoot just before sunrise or just after sunset, you can capture beautiful light without all the really dark shadows (Figure 4.3).
Figure 4.3 The long shadows and warm light of sunset help add depth to the scene.
One of my favorite times to shoot outdoors is during overcast conditions. Actually, let me clarify. If I am shooting landscape images that will include the sky, overcast is not my favorite, but if I'm shooting a portrait or anything else during the day, it will most likely look better under a little cloud cover. This is because the cloud layer is acting like a large diffuser, which spreads out the sunlight and produces much softer shadows and less contrast in the image (Figure 4.4).
Figure 4.4 An overcast sky will help to soften shadows.
With more and more people turning from wasteful incandescent light bulbs to the more energy-efficient fluorescent option, it is more likely than not that you will be shooting under this light source. It used to be that fluorescent bulbs would give off a cool, greenish color cast but now you can find fluorescent bulbs that are balanced for daylight for the home or even for use in a photo studio. As a light source in general, fluorescent bulbs are not that bad to shoot with. They offer a nice bright light that is fairly diffuse, which means lower contrast (Figure 4.5). The one thing you will want to do when using them is to either use the Fluorescent white balance setting on your camera or create a custom white balance setting. Creating a custom white balance is probably the best approach, because the color temperature of the bulb can vary greatly depending on whether or not it is daylight-balanced.
Figure 4.5 With the proper white balance, you can get some nice, even lighting from a fluorescent light source.
When shooting under incandescent lighting, you will find that the light has an orange-yellow color cast. It can also be a much harsher light source since most of the light is emanating from a small point (the bulb). Of course, shooting with the correct white balance is the easiest way to overcome the color issues. Just be sure to preview your results (Figure 4.6).
Figure 4.6 Notice the warm orange color cast on the left that comes from the incandescent lighting. By selecting a Tungsten white balance I was able to capture more accurate colors in the rock formations.
We will cover flash more extensively in Chapter 8, but I think it's important to mention here. Flash can be a photographer's best friend because it is a reliable, predictable, controllable light source that is very close in color temperature to daylight. This means that it can be used to fill in shadows while shooting in daylight conditions without worrying about mixing different color temperatures. The same can't be said for most of the other artificial light sources (with the exception of daylight-balanced fluorescents).
Flash can also be made to take on different characteristics, which can make the quality of light either very harsh and contrasty, or very soft and flat. This can be done through the use of diffusion materials or other methods to create a larger apparent light source (such as shooting your flash through a diffuser or a softbox). You can also color the light coming from a flash using gels, which allows you to match another light source's color or create a special effect (Figure 4.7).
Figure 4.7 A flash fired through a softbox close to the subject provides the main light for this image. Another flash is used to provide "fill light," which lightens the shadows on the left side of his face. Finally, a small flash with a blue gel is used to illuminate the background.