EXPLANATION OF TERMS
Color Temperature
The numerical expression of the tone of the light, produced by a light source. The
standard unit for color temperature is degrees Kelvin (K). The sunny daylight used as
a standard near 5600 K. Low color temperature implies warmer more yellow/red light
while high color temperature implies a colder more blue light.
The typical color temperature of Tungsten light is 3200 K grade, a personal computer
is 9300 K.
Exposure.
The amount of light reaching the image sensor’s surface. The exposure is controlled
by the combination of aperture and shutter speed.
EV
Exposure Value (EV) is a numerical value that expresses the amount of light for a
given exposure, and depends on brightness of the photographic subject and
sensitivity of the film. If a photographic subject is bright, then this numerical value will
be large, and if the subject is dark then this numerical value will be small. If two-times
of light reaches the film surface then the difference in exposure value will be +1, and
if the amount of light is reduced by half, the exposure value changes by -1.
Histogram
The histogram function is a graphic representation of how bright and dark pixels are
distributed in an image. The histogram function enables a precise check on the
exposure of the photo.
ISO Sensitivity
ISO（International Organization for Standardization）; refers to the number assigned to
each silver halide film, which indicates film speed or the film's relative sensitivity to
light, the higher the number, the greater photosensitivity and vice versa. Digital
cameras also use standard ISO sensitivity ratings like silver halide films.
JPEG
Joint Photographic Experts Group has established a standard method for
compressing and decompressing the digitized images. If the rate of compression is
high the file size will be small but picture quality will be decreased.
Microdrive
Developed by IBM, the Microdrives are extremely small-sized hard disks that can fit in
a CompactCard memory slot. The Microdrive is built into a Type II CompactFlash
form factor.
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