I love
photographing flowers. My yard is filled with an assortment
of flowers that range in style and color. Many a time I
am surprised when I view the images in my camera. I have
to run back out and take a second look. My lovely pink flowers
magically turned blue. I have to admit, it is usually a
nice shade of blue, but not an accurate representation of
what I attempted to achieve.
The
two images were taken seconds apart but show different color
tones. Both were taken with the Canon D60 using the Canon
100mm Macro 2.8 lens, at ISO 100. I set my camera to automatic
for Image 1 to show the readings the camera deemed appropriate
exposure for the conditions.
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Image
1: Shutter Speed: 1/125; Aperture 4.5; Full frame; No
Flash |
The
image to the right is actually a pink flower. OK, it looks
bluish and that is because of the color temperature measured
in °Kelvin. Color temperature is simply a way to measure
the quality of a light source and is based on the ratio
of blue light to the amount of red light, and the green
light is ignored.
A light
with higher color temperature (larger °Kelvin value)
has "more" blue lights than a light with lower
color temperature (smaller °Kelvin value). Thus, a cooler
light has a higher color temperature. 5500°K is your
noon daylight or "white" color temperature.
When
shooting in conditions that measure a higher °Kelvin
temperature the photo will look bluer. Below the 5500°Kelvin,
the color will increase in orange tone. I will try not to
get too much into the color spectrum here.
The
first image was taken during midday under overcast conditions.
So what happened? When you have cloud cover, the sun is
obscured and some of the red and yellow wave lengths of
light are absorbed by the water droplets of the clouds.
The colder end of the spectrum, the bluish wave lengths,
pass through unimpeded giving you the bluish color. You
will notice the greenish center, where you should see yellow.
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Image
2: Shutter Speed 1/125; Aperture 2.8, Canon 550EX Flash
Unit Exposure Compensation @ -1.0, Full Frame |
The
second image shows the correct color tones for the flower
(as seen in my garden). Pink is pink, and yellow is yellow,
all as it should be. I used my Canon 550EX Flash unit for
this image to bring in more light. Remember, I shot this
during midday so I did not want a full flash (5500°K)
for this image. I only wanted to compensate for the overcast
conditions. I set my flash compensation to -1.0. I also
opened up my aperture to 2.8 to allow more light to enter
at the same shutter speed.
Every
camera is different in some respects depending on the manufacturer,
but for the most part your camera's automatic White Balance
(WB) is set to 5500°K or daylight. If the conditions
in which you are shooting does not match up, neither will
your colors. If your light is overcast or shaded, you need
to compensate for this by using flash, setting your aperture
to accept more light or custom set your WB.
A better
explanation would involve a discussion on the magnetic spectrum
and how your camera "sees" color (WB). I do not
have the time to get that technical. Hopefully, this article
has shed some "light" on the subject and will
help you to capture those "true colors".
About
the Author
Sue
Alden received her BS from the University of Maryland.
She is now an Environmental Scientist working for the Army
as a civilian and expects to retire in two years. After
retirement, Sue is planning on pursuing a Master's Degree
in Photography. Sue is also a forum and gallery moderator
for www.photomacrography1.net.
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