The quality of light
Do you know the difference between a good photographer and a great one?
It is light. Or rather, the way the photographer uses the available light. A good photographer knows how to compose an image, how to aim the camera so that the viewer gets a complete and unique perspective of a subject. The photographer knows how to capture an event in an interesting and unusual way – even how to capture an emotion.
But a great photographer does all this in the right light. Light is always present around us and therefore you may not always be aware of it. Unless, of course, you get blinded or you end up in pitch darkness.
But mostly light is “ordinary”, so we don't pay much attention to it.
I used to take quite a lot of pictures without really thinking about the quality of the light. Since I started lightpainting, the sense of good light has started to develop better and I notice that my nature and wildlife photography also benefits from this.
Natural versus artificial light
From a photographic point of view, we can divide light into two categories: natural and artificial. Of course, both categories contain parts that they share and sometimes overlap. For example, natural light is usually produced by the sun, but natural light can also come from flames such as a candle or even a forest fire. Moonlight is also a form of natural light.
But while all of these aforementioned forms of light come from natural sources, they have vastly different characteristics. For example, candlelight produces light with an orange tint, while the midday sun produces a much bluer light. Even the properties of sunlight can differ greatly from one time of day to another: for example, morning sunlight is diffuse and produces softer shadows, while the afternoon sun is direct and produces darker shadows.
Artificial light, of course, is any kind of light that is made by humans.
This can range from those noisy fluorescent lights in an old office building to a state-of-the-art set of studio equipment.
Different types of artificial light will also have different characteristics. A bare lamp gives off a completely different kind of light than a softbox. It's also colored differently: most standard lighting is yellowish in color, while photographic lighting is usually balanced to simulate sunlight.
Understanding specific light characteristics and properties will help you, just like it helped me, to take better pictures.
Color temperature
You've probably also heard of this term, perhaps immediately followed by a "huh?" response. How can a color have a temperature?
Extensive technical stories have been written about it, but we will leave them for what they are for now. All you really need to know is that different types of light have different color casts. Is that starting to sound familiar? Incandescent bulbs give a warm yellowish or orange glow and the sun gives a cool bluish glow. The color temperature is measured on the Kelvin scale; for example, a candle's flame is 1200K, which is towards the orangey end of the scale, and a cloudless day is 10,000K, which is towards the blue end.
With modern digital SLR cameras you don't need to know much more, because we can correct the color temperature with the white balance setting.
Many photographers leave this setting on "automatic" (me included), but if you want to fine-tune it, you can tell the camera that you're shooting in daylight or on an overcast day.
Or if you want even greater precision, you can shoot a pure white object and let the camera use that image to calculate the color temperature of the scene.
Some cameras even take it a step further and let you adjust the setting to a specific Kelvin value. You actually need a color temperature meter for this. For most forms of photography, this is an unnecessary step. While modern cameras are quite good at compensating for color temperature, it's important to have a basic understanding of it so you can adjust your white balance as needed.
Light intensity
Light intensity is closely related to light quality. High-intensity light sources usually produce hard light, and low-intensity light sources produce soft light.
But for practical purposes, light intensity usually refers to the aperture, shutter speed, and ISO you should choose for a given scene. For example, in a low-light scene, you have to sacrifice depth of field to achieve a faster shutter speed.
In high-intensity light, you may need to choose a much smaller aperture to slow down the shutter speed. And the intensity of the light also determines the ISO value - you may not be able to hold the camera shake-free in a low-intensity scene if you choose a small ISO value.
In a studio environment, you naturally have control over the light intensity and therefore also have the freedom to set the lighting in such a way that any combination of shutter / aperture / ISO can be used.
You can't do that so easily with natural light, although you can make adjustments with additional equipment such as ND filters, reflectors, etc.
The properties of light
We now turn to three technical matters. To understand light well, it is important that we also have a basic knowledge of the following three properties of light: absorption, reflection and transmission.
Light behaves differently when it reaches different objects. Some objects absorb light, others reflect it, and others transmit it (that is, it passes through). This is basically how color works: an object that we perceive as red actually reflects red and absorbs other colors. True white reflects all colors and true black absorbs all colors. Most objects absorb light.
This includes most subjects in nature; animals, rocks and vegetation. Objects that reflect light well are often objects that we perceive as shiny, such as foil, polished metal surfaces and freshly fallen snow.
However, non-glossy objects can also reflect light – if you've ever bounced your flash off a ceiling or plain white wall, you'll know what I mean. Reflection can be direct or diffuse - a direct reflection comes from a smooth surface such as a car's silver bumper, while a diffuse reflection comes from a surface with some texture. As you might guess, a diffuse reflection produces softer light than a direct reflection.
Objects that transmit light are usually objects that we can see through, such as clear water or glass.
Glass is so perfectly transparent that it doesn't do much for the quality of the light – in technical terms this is called "direct transmission". Its cousin, frosted glass (like that stuff you have in your bathroom) also lets light through but scatters it, softening it. Then there's selective transmission, which is what happens when the glass is colored. An object that selectively transmits light will pass only light that is the same color as it, while reflecting everything else. So the light coming through a green piece of glass will be green, because all the other colors are reflected before they reach the other side of the glass.
What does this mean for you as a photographer?
It means you can use these principles to manipulate light to improve your photos. For example, if you're shooting a subject on a sunny day, you don't have to accept shooting in harsh light.
Instead, you can use a portable reflector to cast light into the shadows of your subject's face. This obviously gives more detail in those shadows. But you can also use a diffuser to soften the light, a semi-transparent surface placed between a light source and the model.
A soft box serves the same kind of purpose: a diffuser between the light source and the subject keeps the light soft and even.
Conclusion
It's surprising how many hobby photographers don't really understand light, and it's even more surprising how many just don't pay attention. All those automatic settings on our DSLRs are both a blessing and a curse – they help make decisions about photography, which is great when we're shooting quickly, but can also be a drawback when we want more control over our images.
Since I started light painting I started to think much more about the light. Every time I took a picture again! Whether I add the light myself or use the natural light as the subject of my photo; light is the most important element in any photo. Ignore it and your images will suffer. Embrace it and you will soon find yourself taking pictures that you never thought possible before.
Do you want to spend an evening actively working with (artificial) light in all its facets? Want to know how to properly illuminate the most difficult situations? Then the light painting workshop maybe something for you.
