Light - How to See It, How to Use It

Light and shade are the fundamentals of photography. In this section you will learn the details of how to understand light and its qualities.

The Qualities of Light

We've talked a lot about exposure, but very little about the "qualities" of light. Light and how to see it, understand it and use it, is fundamental to photography. You want to move beyond just a correctly exposed image to using light and shade to add impact to your photographs. Often it is the shadow, not the light, that really makes the picture.

Light has a range of qualities.

Brightness

Brightness: the least interesting of the qualities, since we can easily adjust exposure to manage brightness.

Contrast

Contrast: the difference in brightness between the lightest and darkest parts of the image.

Sharply defined transitions between light and shade

Transition

Transition: this is how sharp the dividing line between light and dark is. A broad range of tones between light and dark is a "soft" transition. A narrow range is a "hard" transition.

A very wide range of tones, from black through all the greys to near white

Tonal Range

Tonal range: whether there are few tones, say just crisp black and white tones, or whether there is a range of tones through all the shades of grey as well.

specular picture

Specularity

Specularity: not so much to do with the light source, but really about the reflective nature of the subject. High specularity is very reflective. For example a shiny chrome motor bike is highly specular. You want to show lots of reflected, specular points of light to capture this. On the other hand you don't want a shiny bald head on a man's headshot.

Colour

Colour: light is made up of many colours - you've seen the classic prism of light showing all the colour of the rainbow. This is what we understand as sunlight. Artificial light has a different colour spectrum. Although our eyes adjust to this automatically a camera needs help.

A rainbow is a break down of "white" light into its constituent colours. Beautiful isn't it?

If a ball has completely flat lighting then it might as well be a disc.

Light and Shade: The Third Dimension

By its very nature a photograph is flat. Light and especially shade gives some of the sense of depth and shape back to a photograph. The shadows are what tell us about how the image looks in three dimensions. In general flat, even lighting is to be avoided.

Whenever you take an image, look at the shadows. How can you use those shadows to create depth? How can you use those shadows to reveal more about the form of the object? How do shadows tell the viewer about the relative positions of objects?

But has soon as we move the light to the side and introduce shadows it immediately takes on a three dimensional shape.

The deep shadows both frame the image, give strong lines through the images and stop us looking for faces.

Managing Contrast

On a bright and sunny day the first thing you will see in your photographs is that the shadows are very dark. This is because there is a strong contrast between the light and dark.

You can use this contrast to good effect on the right kind of shot.

If you want to reduce contrast though you have two options. One: reduce the bright light or two: add some light to the shadows.

The shaded face on the right still has her eyes wide open

Contre Jour

When shooting people outdoors there are some very simple things you can do to remove bright light. Firstly turn them so their backs are to the light. This will stop them squinting and having "racoon" eyes.

Full back lighting and some lens flare gives a washed out look - but which works perfectly for this evocative image.

The backlight (called contre jour) is also a nice effect in its own right.

Secondly you can move them to a shady position. The shade stops the direct sunlight. The shade does not need to be in shot, just as long as it falls across the subject.

Reflectors

You can add light back in using a reflector. This can be anything from a white card or cloth to a professional reflector.

By adding light back into the shadows you reduce the contrast. The reflected light will not be as strong as the main light, so still keeps a sense of shadow and shape.

The hard light here has created a wonderfully dramatic portrait shot of this cat

Hard and Soft Transitions

Soft transitions are what you would normally look for. A soft transition is not obtrusive. However hard transitions can add a lot of drama to a photograph.

You would normally use a combination of hard transition and high contrast to create a dramatic image.

To create soft light the light source must be very diffuse. Think of a hazy day, or light coming in from a north facing window.

To create a hard light the source needs to be small and far away. Think of direct sunshine - or your camera flash.

Using Window Light

To take a window portrait shot you would normally use the soft light of a north facing window. This gives soft, appealing tones, particularly for women and children. You would not face the person directly into the sunlight making them squint.

The direct sunlight gives both a hard light and high contrast.

Sunshine direct through the window creates hard shadows and high contrast.

You can position your subject in front of a bright window to create a contre jour effect indoors.

With the back to the window we create a lovely rim lighting effect around the body

The soft lighting really supports detail in the shadows, but at the same time gives a full 3D shape to everything in the picture. Some nice post-processing has finished this off perfectly.

If you are shooting still life, then you would normally setup a fairly low contrast, soft transition lighting.

Specularity

In most cases you want to avoid harsh points of light. They would tend be a distracting point in the image. But if you are shooting a shiny object, then you want to bring that shine out. You might do this by using several artificial light sources or reflectors. You might use a special effects filter called a "starburst" filter to exaggerate the specular points.

Gorgeous reflections and sparkles on this motorbike

Six Qualities of Light

Understanding Colour Temperature

We think of sunlight as being normal light, yet we can move from outdoors to indoors under artificial light and everything looks the same. Again our eye/brain combination is performing amazing feats of translating relative colours to something we think of as absolute.

But if you've ever bought coloured clothes that looked great in the shop, but completely different outdoors, you have experienced that shift in colour spectrum.

Film and digital sensors can't do this clever adjusting. They record what they see. An uncorrected picture with fluorescent light looks horrible.

This uncorrected fluorescent has a bad colour cast to it and I don't look well at all!

The top half is a true spectrum. The bottom half has lost nearly all the green component. You can see what a big shift in colour it makes.

Colour Spectrum

What is happening is that instead of getting a complete spectrum of colours we are only getting partial spectrum. Some parts of the spectrum are stronger, others missing altogether. So we might have a lot more green in the spectrum, but very little red. This means we get a cool and green photograph.

Digital cameras can compensate for these different spectrums. The default setting on your camera will be "Auto White Balance" (AWB). The camera looks at the scene and sets an average colour to what it sees.

Like all "auto" functions it works most of the time. But if you have a scene where a single colour dominates the image then your camera will get confused.

In trying to render the strong red as a neutral grey the whole image has had to shift to a very blue image.

White Balance Presents

To give your camera a strong assist you will be able to set the camera according to the lighting conditions. You will have white balance for some or all of these options:

Sunlight
Shady
Cloudy
Fluorescent
Tungsten
Flash
Custom or K

When shooting under certain lighting conditions just set the white balance to match your circumstances.

Interactive Example

Use the slider to see different examples of white balance.

Auto: has done an OK job, but Leah looks a little pale

Sunny: is a little better, but still the skin is pale

Shade: gives a much warmer tone to the skin

Cloudy: is somewhere between sunny and shade

Flash: tries to emulate sunshine, so we see a very similar tone

Fluorescent: is clearly way off since we are not in fluorescent light

Tungsten: the same, very out of balance.

The "golden Hour"

On a good day you get two "golden hours". These are the hours around sunrise and sunset. Everything takes on a lovely golden glow. This is because as the sun rises or sets less blue light gets through the atmosphere.

This is a gorgeous, flattering light for many subjects. People look great and warm, colours look stronger. Shadows are stronger and more interesting.

If your interest is landscape photography, then you'd better get used to getting up early. For landscapes the sunrise is the better time. The air is still and clear and if you are lucky you'll get a little mist rising... Everything will look terrific.

While the landscape sunset can be dramatic, often the heat during the day causes haze and dust to rise; wind will come up so waters are not still. Worse, there's a good chance you will have people in your shot!

If your interest is people, then you're probably using the sunset - unless you can talk people into getting up a 5am!

Why Isn't My Snow White?

If your pictures of snow are coming out blue, then that is a white balance problem. Your camera is trying to compensate for all that white and introduces more blue into the scene. The quick fix is switch to "Cloudy" setting.