Light for Photographers
Written by: Colin Aiken
Photos by:
Ryan
Light
is the essence of photography. It’s not things that
we photograph, but the light they reflect. Without
light, there is no photography and the way things
look to us and the camera is entirely dependant on
the light that reaches them.
People talk about the “quality” of light, but in
fact this is a combination of four different things
that all light sources possess. Every light has a
level, a colour, a direction and can either be hard
or soft. Unless you are working in a studio, where
you have total control over the lighting, the first
thing any photographer should do is to make an
assessment of the light in terms of these four
aspects.
The first one, level, is the simplest. Except for
the fact that we are not really aware of it
ourselves. We can easily move from outdoors to
indoors without realising just how dark it is
inside, but the camera can’t do that. Not without
making adjustments. Fortunately, all digital cameras
have an auto-exposure system that will make these
adjustments for you, or you can go manual and do it
yourself.
When the light level starts to go down there are
three things that can be adjusted. The ISO number
represents how light-sensitive your camera is and
setting a higher number will make your camera more
sensitive. The aperture is a hole in your lens that
you can make larger to let more light in. In this
case, a lower number means a larger aperture. The
third adjustment you can make is to the shutter
speed, exposing the image for a longer time.
Whilst
the ISO number and aperture have their effect on an
image, it’s the shutter speed that finally
determines just how low you can go in terms of light
level, without adding your own light. Although you
can set a shutter speed of half a second or longer,
there is no way you can hold a camera steady for
that length of time. If you try, you will get
“camera shake” which hardly ever looks good. Even at
1/30th of a second, you will still get camera shake
unless your lens is zoomed right out to its widest.
There is nothing stopping you taking photographs
like this but you will need to use a tripod or other
stable means of support to avoid camera shake.
Alternatively, you can switch on your flash but that
will now be the main light source and the photograph
will look totally different. Change the lighting,
change the picture.
The second aspect to consider is the colour of the
light. This is similar to light level in that we are
hardly aware of it and our cameras can be set to
automatically or manually compensate for it.
Daylight is blue compared to indoor artificial
light, which is more yellow or orange in colour.
It’s not usually a big problem because even if you
or your camera get the colour setting wrong, you can
still edit this after you have downloaded the images
into your computer.
Where you really have to think about the colour is
when you have mixed lighting. That is, your scene is
lit by two or more sources of light that are
different colours. Imagine a room with bright
artificial light and a window. The light in the room
is yellow and that coming through the window will be
blue. There is nothing that can compensate for two
different colours, you need to make a choice. If you
were photographing someone in this room then where
you placed them would alter their colour. The nearer
they were to the window then the more they would be
influenced by its blue light and vice versa.
Also,
where you place the camera is important. If you are
near the window, facing into the room, then your
main light will be blue and the background of your
subject will be yellow. If you are further into the
room, facing the window, then the opposite will be
true. Given that you, or your camera will adjust the
colour to make the person look right, you are more
likely to be aware of the background colour in the
final shot. One thing that seldom looks good is when
the window is at 90 degrees to the camera, one side
of your subject will be blue and the other will be
yellow and there is no way to compensate for that.
The level and colour of light are important, but
these are things that you simply adjust the settings
in your camera to compensate for. It’s when you
start to consider the direction and softness of
light that you can begin to get creative and really
use the light. A light is called hard or soft
because of the shadows it produces and the governing
factor here is the size of the light source. The
sun, a flashgun or a spotlight, being small, produce
hard, sharply defined shadows. Whilst a cloudy sky,
being big, is a very soft light source and produces
hardly any shadows at all.
When you are making an assessment of the natural
light around you, the first thing to realise is that
there is never only one light source. All light
travels in straight lines, until it hits something.
It then bounces off. If it hits a shiny object, it
will bounce at the same angle it arrived at, like a
billiard ball off a cushion. If the object is matt
(i.e. not shiny), it will bounce off in all
directions and pick up the colour of whatever it
hit.
A single bare light bulb will create a hard light
directly on your subject. At the same time, it
creates a soft light by bouncing off the walls,
floor and ceiling. The lighter those areas are, the
more soft light will be created. If one of the walls
was white and the others dark, then most of the soft
light would come from the direction of the white
wall.
A
hard light source will create very dark shadows,
much darker that we see with the human eye. This can
cause a problem for photographers because, at the
correct exposure, it may not be possible to see any
detail in the shadows. The two ways of dealing with
this are to hide the shadows or fill them in. You
hide shadows by keeping your subject away from any
background and shooting from the same angle as the
hard light source. That way, most of their shadow
will be hidden behind them.
You fill in the shadows by using anything large, and
preferably white, that the hard light is hitting.
This will be a source of soft light and, if you keep
it on the opposite side of your subject to the hard
light, it will fill in the shadows, allowing you to
photograph the details. It is always a good idea to
take a reflector with you (anything large and white)
when shooting on a sunny day.
As you might expect, the direction of a hard light
source is much more critical than that of a soft
one. In fact, changing the angle between your
subject and the light source can totally transform
the way it looks. If your subject has a rich
texture, that can totally disappear when the light
is square on to it. The more oblique the angle, the
deeper the texture will appear.
For portraits, a frontal light will make people
appear less wrinkled and happier. As the light moves
to the side, they will look more serious. Light from
above is seldom flattering and light from below
makes people look downright weird. If you like
landscape photography, try to visit your favourite
spots at different times of the day and see for
yourself the complete transformation that the angle
of light makes to a photograph.
Using natural light doesn’t mean that you need to
put up with bad lighting. By making a thorough
assessment of the light sources around you it is
possible to make the best use of what nature has
presented you with.
Colin Aiken is a professional photographer based in
the United Kingdom. You can view his photographs and
get more tips at:
http://www.lovethepictures.co.uk
|