The sun was striking these still-green leaves on a bough backed by brilliant color and stark trunks. The difference between the bough and background was about 1.5EV, but reading right off the bough made the colors in the background to go darker, which created a strong play of brightness and color.
As the term implies, backlight is a strong light behind your
subject as it faces the camera. In some cases it can cause exposure problems,
but it is also one of the most beautiful light sources for translucent subjects.
Think of stained glass windows in a church. They are rather dark and dull when
the sky is overcast, but when the light comes through them they are the most
glorious window treatments of all.
Backlight is inherently contrasty, meaning that there will
be a considerable difference in exposure between parts of the subject and the
light behind it. In some instances this means that parts of your subject will
either sit in silhouette (having form but no detail within the form) or be
considerably underexposed. The key to backlighting is to exploit this contrast,
to use the shadows it “throws” toward the camera as part of the composition.
You do this by biasing exposure toward the brighter light. The usual solution
to getting detail in a subject that is backlit is to use flash to “fill” the
foreground subject with light, but that defeats the purpose and dramatic
potential of this kind of lighting.
Tools and techniques: spot metering
mode, exposure compensation, autoexposure lock.
The bright light here is supplemented by reflections off the pond, which provides a natural fill light for the darker parts of the scene. Nonetheless a spot meter reading of f/16 at 1/250 second at ISO 200 was made directly off the bright yellow leaves on the left side of the frame.
Perhaps the most colorful season in which to exploit
backlighting is fall, when brilliant color displays combine with low angle
light. The key to exposing this type of lighting is to avoid bringing shadow areas
into consideration and read from the backlit leaves themselves. This is easily
done by using spot metering mode and locking exposure on the brilliant light of
the leaves. In most cases this will be the proper exposure, but in some
instances you might want to use a + exposure compensation to add some
brightness to other parts of the scene. This rarely goes above +0.5EV. Once you
attain the exposure and review it to make sure it does the job, lock it, or
switch to manual mode to maintain the exposure as you work in the area.
If you are shooting in the shade with a bright sky behind
the main subject you can either crop out the sky and not worry about contrast,
or expose for the main subject and deal with the bright backlight later in
processing. These formations sat in deep shade but I wanted the sky for relief
of the forms at the top of the frame. I used CWA to make the exposure, locking
it on the formation itself, then recomposed. Later in post I selected the sky, which
was blank in the recording, and added a very light blue color wash.
There may be times when working with backlight that the sun
is higher in the sky and/or cannot be absorbed by a dense background. It is essential to then make sure you block
the sun from both the image and from exposure consideration. I often do this by
finding a shadow area cast by the foreground subject and stand within it to
make the picture, or at least position myself so that I block the sun with a
branch, rock or other obstruction. Failure to do this will result in flare and
an exposure that is thrown off by the strong presence of a direct light source.
In addition, it is never a good idea to look through the finder directly at the
sun. In this shots I used a branch to black the sun and took my
spot reading from the leaves of the center tree.
