Task 1
Light and Color
Light is a type of electromagnetic
radiation. Electromagnetic radiation is made up of waves that transport energy.
This energy travels in tiny packets known as photons. There are many different
types of electromagnetic radiation, and together they make up the
electromagnetic spectrum, which includes: radio waves, microwaves, infrared
waves, visible light waves, ultraviolet waves, X-rays, and gamma rays. Waves
can be measured by their wavelength (the size of the wave) and frequency (how
many waves pass a point during a time interval). All of the energy inside a
photon has its own wavelength and frequency.
….photons of visible light (light that
humans can see) have wavelengths of 400-700 nanometers (10-9 meter or
billionths of a meter), and a frequency of 430-750 trillion (1012) cycles per
second….
….The light from the sun contains
millions of photons of variable wavelength, not all of which are visible to
humans. Within the range of wavelengths that make up visible light, different
wavelengths correspond to different colors. The light seen from the sun appears
white, as it contains all wavelengths and thus all colors. (Imagine a prism
breaking white light into the colors of the rainbow.) When photons hit an
object, they may be absorbed, transmitted or reflected. An object appears a
certain color when all other wavelengths are absorbed except the color being
seen, which is reflected. For instance, plants appear green, as they contain
chlorophyll, which absorbs red and blue light and reflects green light. Objects
that appear white reflect all wavelengths, while objects that appear black
absorb all wavelengths…
(Professor/Scientist of How Stuff
Works.co, Australia)
All
type of light is not same, they have different value of contrast and brightness
There is a variety in the color makeup
of light that appears white. Sunlight is almost perfectly balanced light
source—it contains all colors in nearly equal quantities. But daylight does
experience color shifts. The color appearance of objects changes dramatically in
early morning or in the shade. Electric light sources can also exhibit
variations in color makeup. Incandescent lamps tend to produce more red and
yellow light than green and blue, and appear to be “warm” in color. Because of
the way incandescent light is produced, little can be done to manipulate its
color characteristics. With fluorescent and high intensity discharge
lighting, this latest technology makes it possible to manipulate the color
makeup of a given light source.
Picture 1: image of a
cartoon figure under a spot light |
|
Picture 2: image of the
cartoon figure under fluorescent light
|
|
Picture 3: image of the
same cartoon figure under sunlight
|
The difference between this two images is the
quality of the sharpness of the color. As in the picture 1, the photo seems to
bring up a thick contrast point on the subject matter. This is because the
direct light (spot light [LED]). Moving to the other picture (picture 2), this
photo is good in color for the subject matter. The problem is, it does not have
any saturation quality on the subject matter. Besides, the yellow color of the
object looks dull. This two results are totally different when the photograph
is taken under a sunlight. As we see in the picture 3, direct sunlight shows and
highlights the originality of the color on subject matter.
White
Light and Bright Colors
Generally speaking, whiter light
(comprised of equal amounts of all colors) makes colors appear more natural and
vibrant. However, some portions of the spectrum are more important to a light’s
color makeup than others. Red, blue and green—the primary colors of light—can
be combined to create almost any other color. This suggests that a light source
containing balanced quantities of red, blue and green light can provide
excellent color appearance even if this light source is deficient in other
colors in the spectrum.
Conclusion
In a process of documentation or
photographing an object, the image quality in point of contrast, brightness,
saturation level of color and the levels of each color angle is depend on the
type of light where the photo session is taken place. This is because, not all
the object is suitable for all type of lighting especially fruits in high rated
color. Besides, the wavelength of all light is not balanced as wanted to
imaging an object.
Reference:
Picture 1, 2 & 3 :
Images from mobile
phone