Focus On Lighting Photos Focus on the Fundamentals.pdf

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what are “degrees KeLvin”?
Kelvin is a temperature scale,
like Fahrenheit, Centigrade, or
Celsius, but Kelvin also measures
color. If we heat anything
enough, it will glow. The more
we heat it, the bluer its color.
Of course, if we heat anything
too much, it’s likely to burn.
So we heat things in a vacuum.
Without air, the thing we heat
can’t burn. That’s why our old
tungsten lightbulbs are made
with as little air inside as possible.
That allows us to heat the
tungsten up to about 2800°K
without immediate burnout.
The Kelvin scale is counterintuitive
to most people. The colors
that artists call “cool”—blues
and greens—have a higher
(hotter) Kelvin temperature,
whereas the colors we call
“warm”—red, yellow, orange—
have a lower (cooler) Kelvin
temperature.
For a simple explanation,
ignore fluorescent lights. They
are also measured in degrees
Kelvin, but there is more going
on there than Dr. Kelvin’s old
heat principle.
<strong>Focus</strong> <strong>On</strong> <strong>Lighting</strong> <strong>Photos</strong>
It’s always
better to
make color
adjustments
in the camera
rather than later
with software!
Pretty much every digital camera
today comes with settings
for Sunny, Shade, Incandescent
(Tungsten) modes, and some
even accommodate various
fluorescent light sources. (These
terms may vary from brand to
brand.) They also usually have
an Auto Balance (Auto White
Balance) setting where the
camera automatically takes the
amount of light and its color
information and provides a
natural white balance (not always
reliably). Many cameras also
allow us to create Custom White
Balance (handy if we are using
old softboxes or diffusion materials
that have yellowed with age).
Some cameras will also allow
us to actually enter the Kelvin
number we want.
When we want the image to be
as close to the way we perceive
the scene, we’ll want to be sure
to set the camera to match our
light source. If we don’t, we’ll
get a photo that doesn’t look like
what we anticipate. We can mix
and match if we want to have fun
or create a mood, but if we’re
looking for “reality,” then we
have to learn to recognize our
light sources.
We generally consider midday
light on a clear day to be
“normal” lighting. Most flashes
are set to approximate this color
of light. However, daylight actually
changes based on the time of day,
whether the subject is in shade
and whether there is cloud cover.
It can be very blue, red, or orange.
So now we know sunlight
changes color during the day.
When the sun strikes the subject
directly, we see warmer light.
When the day is bright but the
sun doesn’t strike directly, the
color is cooler. Why? Think of
a white building in an open