While the human eye can easily adapt to the changing shades
of light, the camera is a little more complicated. Because of this, you must
tell her yourself when she recognizes colors unrealistically. This is done by
adjusting camera modes or automatic white balance. How to fine-tune the colors
of the scene so that they correspond to reality?
White Balance Settings
Digital photographs consist of information about shades
(brightness) and colors. The tones in the photo are controlled by the exposure
settings of the camera. The main tool for managing photo colors is setting the
white balance.
Color of light
Different light sources have different shades. The human
brain effectively adjusts color perception to account for this. For example,
when the light of an incandescent lamp falls on a sheet of white paper, it
“stains” this paper in orange. The brain knows that a piece of paper is
actually white, and therefore, in a person’s perception, it automatically
corrects the color cast caused by the light source.
But the camera does not work this way. She captures the
actual color of the light, so she needs to somehow tell whether the colors of
the scene are shifted.
The easiest way to see colors in individual light sources is
to take an evening walk around the city. Your brain will be tuned to external
light, and when you look through the windows of apartments and houses, you will
see orange light from incandescent lamps, blue light from any CRT TVs that you
can still encounter, and green light from fluorescent lamps.
Color temperature measurement
Color temperature is expressed in units of temperature to
which a “black body” (an object that does not reflect light) must be heated so
that it begins to emit light of this shade. Color temperature is measured in
Kelvin. When you heat a black body, heat gradually turns it into red, orange,
yellow, and white, until it finally turns blue at the highest temperature.
Thus, the color temperature scale is the opposite of how we
are used to perceive colors. Warm shades (red, orange) have a lower color
temperature than blue, which we usually consider to be cold.
When shooting, you must directly or indirectly tell the
camera what temperature in Kelvin your lighting has. Then the camera processor
includes this information in the final coloring for the photographs you took,
and they look realistic, without color shades. Although this sounds rather
complicated, in practice everything is simpler.
To "warm" your images, set a higher temperature in
Kelvin in the settings. To "cool" - set a lower temperature. Keep in
mind that some cameras do not have the Kelvin scale option in the white balance
setting. If so, you can use the white balance presets, which we will talk about
below.
White balance adjustment (setting the correct color temperature)
Auto White Balance
Normally factory-set, your camera uses AWB (Auto White
Balance). These sophisticated embedded systems in cameras automatically
determine the color temperature of the current lighting and based on this set
the white balance. As with automatic exposure settings, this method is
successful in about 90% of cases, and you can usually rely on it. In situations
with difficult lighting, you have several ways to influence the .
white balance setting
Using AWB. The camera’s automatic white balance appreciated
this scene and set the white balance “correctly” to get a blue sky. However,
the colors of the photo lack the mood that was originally. Canon EOS 7D, EF-S
15-85 / 3.5-5.6, 1/640 s, F16, ISO 100, focus 42 mm (equivalent to 67 mm)
Manual Presets
The easiest way to influence white balance is to use presets
in the camera. Standard white balance presets have names such as daylight,
cloudiness, shadow, tungsten (or an incandescent lamp), fluorescent light, and
flash. Using one of these presets, you select the color temperature, which,
according to the manufacturer, is suitable for the situation described in it.
For everyday photography, they are quite enough. But when you need to set the
white balance more precisely, there are special tools for this.
white balance setting
The same scene as in the previous photo. White balance was
set to Cloudy. Now the sullen colors of the sunset were captured correctly.
Canon EOS 7D, EF-S 15-85 / 3.5-5.6, 1/640 s, F16, ISO 100, focus 42 mm
(equivalent to 67 mm)
Let's look at each of the white balance presets.
"AWB" is the auto white balance setting. Select
this preset so that the camera’s light sensor can select the best white balance
setting based on the color of the available light. AWB helps in mixed lighting
conditions.
“Custom” - select this option to set your white balance
value for the color of the available lighting.
"Kelvin (K)" (Kelvin) - you can select the white
balance based on the temperature scale in Kelvin. Choose a larger number to
remove the cool color cast from the images (add warmth), or select a lower
number to remove the warm color cast (add the blue).
Tungsten - Select this preset if you are shooting with
household bulbs as a light source. Or, if you notice that your images have an
orange tint, select this option to remove it.
"Fluorescent" (Fluorescent) - used when shooting
under fluorescent lighting. Or, if you find that your images have a green tint,
select this option to add magenta to balance it.
“Daylight / Sun” - When shooting on a bright sunny day,
select this preset. Or, if your images have a slight blue or orange tint,
select this option to balance this.
“Flash” - the preset is the same as the “Daylight / Sun”
option, but it is here so that people using the flash know exactly what to
choose.
Cloudy - If you are shooting on a cloudy day, select a
preset to balance the light. Or, if you find that your images have a cool color
cast, select this option to add warmth to them.
“Shade” - when shooting in the shade or in very cloudy
conditions, select this preset. Or, if your images have a bright blue tint,
this option will help balance it.
Fine (gray card, expodisc)
Each camera processes the picture a little differently; You
need to know how this is done specifically for your model, so read about it in
the user guide. A gray card (a cheap solution) or, for example, a special white
balance filter (Exposure Disc) is well suited for work.
White Balance Bracketing
If you're not sure which white balance is best, some cameras
can help with white balance bracketing. In this mode, pressing the shutter
button “forces” the camera to take three pictures. One is based on the white
balance setting, one cold shot and one warm shot. Then you can choose the frame
that you like best.
White balance bracketing on a Canon EOS 60D SLR camera.
Bracketing can also be combined with white balance correction.
Difficult lighting conditions (mixed lighting)
It’s easy to work with
if you work with one light source or several sources that have the same
color temperature. But photographers have to work under lighting conditions
with several sources with different color temperatures. The solutions for these
situations are different. For example, if you are photographing at a concert ,
then colored lights are part of the show, so it is best to balance daylight and
capture the chromatic atmosphere of the show.
If you shoot in a room with a mixture of fluorescent and
daylight penetrating through the window, you will need to balance both sources
... which is impossible to do in the camera. In difficult situations like
these, you have to turn to the photo editor. The simplest and most popular
solution is to convert the photo to black and white. To actually preserve the
colors in the photo, you need to use local color changes.
Computer white balance
All of the above
information is especially important if you shoot in JPEG format . JPEG
files come from the camera in compressed and fixed colors, which their camera
took. If you photograph in RAW format, you can change the white balance without
losing quality, you have much more freedom.
White Balance on the Creative Side
You do not always need to use to get the technically correct colors. You
can also use them to deliberately shift the tone of the image towards warmer or
colder shades to give the picture an unusual atmosphere.
One of the most popular techniques of portrait photographers
when shooting in the daytime is to intentionally set the white balance to
“Cloudy”. This gives a warmer picture, which is a plus for portraits . Warmer
skin colors make the portrait more vibrant.
There are many tools for precise white balance. The simplest
of these are standard gray cards .
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