Light is the fundamental tool for photography that every photographer should understand well. As a photographer, the way you understand light is very different to how everyone else understands light.
(Grains lit by hard sunlight – Nikon D200 with Nikkor 18-35mm lens, f/11, 1/25, 100 ISO)
Light has some well defined values to it. The most important is the amount of light. As is obvious, the higher amount of light translates to low ISOs, fast shutter speeds and small apertures. (Basics of Exposure) When someone a photographer says that the light is good, what does it mean? It does not just mean that the light is bright or the amount is good enough. Here comes another factor into play. This is called the quality of light.
The light which creates sharp shadows is called hard light. Hard light is good for bringing out textures and showing a range of brightness values in a photograph. (Photographing Texture) Quite frequently photographers use hard light to enhance the wrinkles on an old face or to give a feeling of depth to a monument. Light which spreads all around and does not create very sharp shadows is called soft light or diffused light. Soft light is favored when there is a need for a more even illumination of the subject. For regular studio portraits, this is what photographers as well as the models prefer. Soft light also hides minor flaws in the faces and provides an overall pleasing effect.
Distance from the subject is the major factor that determines if the light is soft or hard, apart from also determining the total amount of light falling on the subject. The farther away a light source is from an object, the harder its light will fall it. Direct sunlight is hard. It creates shadows, does it not? Size of the light source also matters. Large sources of light provide soft light. Small sources provide hard light. One of the many reasons why I hate the built-in flash of the cameras is the small size. They provide very hard light. Light from a large window with frosted glass panes will be very soft light for a subject close to the window.
Converting hard light to soft light is an easy task in controlled set-ups. All that is required is to increase the area from where the light is being thrown out. If it is a flash, placing a large translucent cloth in front of it, at some distance helps. Bouncing the flash from a wall or ceiling also effectively increases the area of the light source thereby softening it. Softboxes, studio umbrellas and even reflectors do the same thing. On an overcast day, the cloud cover acts as a large diffuser for the sun. Photographers in general love overcast days for photography.
(Soft light on an overcast day illuminated the flower completely. With hard light, the ladybird in the center would have merged with the shadows)
Understanding the limits of a medium
Though the world around us has a huge range of bright and dark values, our cameras are not that capable. There is a limited range which they can capture. Usually this range is quoted in terms of Exposure Values (EV). This range is also called the dynamic range of the camera. (In the film era, it was the dynamic range of the film). Dynamic range of around 10 EV is common in most cameras. Some newer cameras have still higher dynamic ranges. What it means in simple terms is that the darkest value that a camera can capture is about that 10 stops lower than the brightest value it can capture. If a scene has a range of 15 EV, then in such a camera, 5 stops of light can’t be captured. Either the information in the brightest portions will be lost (also called clipping in photo-processing lingo) or if the exposure is towards the brighter side, then the dark areas will face the same problem.
Ansel Adams (Ansel Adams – His Influence), the famous photographer, had come up with the Zone System to deal with this problematic calculation. By carefully reading the light values from the various parts of his subject, he could calculate the exact exposure to get his subject perfectly exposed and centered in the dynamic range. The same method can be followed now with digital cameras also. Try taking a spot meter reading from the brightest part of your image and then another reading from the darkest part of your image and then try to set the exposure. I have found that though this is a time taking procedure, the results are better than even while using the most advanced 3D matrix or evaluative metering modes. (Metering Modes) I reserve this method for capturing landscapes and similar ‘not too fast changing’ subjects.
(A tricky exposure. I wanted to capture the grass as well as keep the opposite river bank dark. The 3D matrix meter worked well though I had to dial in a -1EV compensation. Using a spot meter from various parts of the image would have worked better but then the droplet that fell on the water needed a fast click)
Observing the scenes around you is the first thing to do. Look around you. Find the brightest object (except the light source itself). It maybe a white sheet of paper on your desk or a stack of visiting cards under your table lamp. The brightest object may just be a part of the floor where direct sunlight is illuminating it. Whatever it is try to write down a list of ten objects in your room from the brightest to the darkest. Cross check with your camera’s meter how correct you had been. Try doing this exercise in your free time, at your office desk or even while waiting for your date. Within no time, you’ll start seeing the light values in a scene. For an unaware person, the brightest object in a room may be a white cloth but for you as a photographer, the brightest object may be a dark metallic statue reflecting the sun-light from some of its parts. Learning to see the light values helps.
Thinking in black and white is another helpful way. Click black and white images exclusively for a few days. (Black & White) Keep checking your results. Very soon, you’ll start seeing the light as it exists.
Thanks to the proliferation of advertising industry, lots and lots of photographs can be found in print. Pick up your favorite magazines and for a change, observe the photographs in the advertisements. No, not the articles that interest you but the advertisements. Try to understand the way those models or products were illuminated and the direction of the light. This will give further understanding of the way light works for photographers. Being a self taught photographer, the first trick that I mastered from such magazines was highlighting the hairs of a model by throwing the light on the head from up and behind a model. Some experts also call it the Rembrandt method of lighting.
After all, photography by itself means ‘drawings of the light’. Befriend light and you’ll be one step closer to becoming a photographer you aspire to be.