How to deconstruct light (Part two)
This is part two of a two part series on deconstructing lighting. You can see part one here.
Shiny Objects and Bright Eyes
While shadows can provide useful clues as to how a subject was lit, so too can another common feature within many photographs and art works - specular highlights.
The word “specular” means to have the properties of a mirror, and as you might guess, specular highlights occur whenever an object or a surface within a photograph has reflective qualities. One of the most classic forms of specular highlight can be seen whenever you are photographing a sunset over a lake or the sea; the sunlight is reflected across the surface of the water, and often it can be as bright and dazzling as the sun itself.
At a more subtle level though, specular highlights can occur wherever there is a mix of moderately directional lighting and a reflective surface. At the human level, specular highlights are often seen whenever someone with slightly oily or sweaty skin has been photographed in direct sunlight or with a flash. Specular highlights will also be noticeable whenever you happen to be looking at photographs of metallic objects or glassware.
Now, the wonderful thing about specular highlights is that, like shadows, they too can offer useful clues as to the direction and quality of the lighting within an image. If you were taught physics at school you will have learnt that “the angle of incidence equals the angle of reflection”, which is to say that if a beam of light happens to strike a reflective surface at a particular angle, it will bounce through and continue on its trajectory at a similar angle.
As with the sundial analogy we used with shadows, we should be able to look at highlights on a spherical surface (a head for example) and ascertain where the main lighting was to illuminate a scene. Also, by gauging the size and brightness of a highlight we can also determine whether the main light source was hard or soft; hard light sources often appear as small bright highlights while softer light sources have a softer but broader presence.
When it comes to deconstructing the lighting of a portrait, one of the most useful places to look for clues is within the eyes of the subject. Eyes are both shiny and spherical and if there is enough detail within an image to have a moderately close look at the eyes, we can often tell both where the light was when a portrait was made, and gauge the size of the light source.
The simplest way to do this is to imagine the eye as a clock face; if the brightest highlights are in the 9 o’clock to 11 o’clock position of the eyes, we know the main light was positioned to the left of the subject, if the highlights are in the 1 o’clock to 3 o’clock position the light source was to the right and if the highlight is near the top of the eye, the light source was above the camera.
Based on the size of the highlights we can also gauge whether the light source was hard or soft. Very small, bright highlight in the eyes indicate that a hard light source was used to make the photo, while if the highlight appears to cover a wider area on the eye, we can assume that a soft light was used to make the image.
If you can see two similarly bright highlights on either side of the eyeball you can assume a photographer had two similarly powered light sources on either side of the subject, although two catchlights in the eye is never that flattering.
If you look even closer at the eye, you can also see if reflectors have been placed when making the image; often a reflector will be placed on the opposite side to the main light to fill in the shadows, and sometimes you will also see a reflector placed beneath the subject, (which will be revealed in the lower half of the eye), again to reduce the effect of shadows.
Reflected Light
Interesting photographs are often interesting because the lighting within a scene is more complex than we might expect. Rather than just one light source, the light might appear to be coming from multiple directions. This is where we need to know another very important fact about light - it doesn’t bend around corners.
Light travels in straight lines, and if light seems to be illuminating more than one side of an object at once, its either because multiple light sources at work within the scene, or light from a main light source is being reflected back at the subject by environmental or other reflective causes.
More often than not, it is this latter reason that explains why light often seems to be coming at an object from multiple directions. In our everyday world, reflected light is everywhere; it is the reason we can see our environment even as we wander through shaded alleyways or beneath the canopy of trees.
One of the nicest examples of reflected light at work can be seen whenever there is a new moon in the sky; for a couple of evenings every month it is possible to make out the dark side of the moon as a faintly lit disc behind the crescent of the new moon. But what’s illuminating the dark side of the moon? It’s our own planet reflecting sunlight back towards the moon.
By comparison to the hard light of direct light source, reflected light is often very soft; in fact, the light is so soft that there are almost no noticeable shadows or highlights within the scene. This soft reflected light is easily found in areas of open shade, but you can also find this soft light at dawn and dusk when the sun is just below the horizon.
In both instances the soft scattered light helps to eliminate shadows and highlights while in many instances flattering the subject.
Professional photographers regularly use reflectors to bounce light from the main light source back towards a subject, in part because reflectors provide a more natural form of fill light.
As with the main light source though, the size, quality and position of a reflecting surface can have a dramatic effect on an image. A large white reflector held near a subject will reflect a soft mellow light back at the subject, but a small metallic reflector (or a mirror) will produce a hard light.
Some of the best famous photographs have often been lit with just the one light source and the clever use of reflectors.
Additional Light Sources
Sometimes reflected light isn’t enough to provide the sort of lighting or modelling effect a photographer wants, and in these instances a photographer will often add additional light sources into their photograph.
In a studio situation, this might mean adding extra lights to illuminate a background or add separation between different components of an image. Outdoors though, a photographer might use a location strobe to provide some hero lighting onto a subject.
The best way to gauge whether a photographer has used additional lights within an image is to try and recognise the different elements within the photograph, and then determine how each of these elements could have been lit.
Again, look where the shadows are falling or the highlights are shining and then use this information to decide whether one light could be responsible for what you are seeing, or whether multiple lights are a play. It is all a case of quiet detective work, but with practice it will all start to make sense to you.
Putting it to Practice
Having spent time looking at photos and trying to deconstruct the lighting, the next step is to use this know with your own photos. This is where things get very interesting - if you can deconstruct the lighting in photos, you can then start learning to deconstruct light as you work with it in the studio or on location.
We will explore this in another story, but no matter where you are or whatever you are doing, remember that you can always pause for a moment and look at what the light is doing about you. Learn to see the light, and you will become a better photographer.