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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.
NTSC
National Television Standards Committee (NTSC) video format is primarily
used in the United States, Japan, Canada etc. The NTSC is a standard for
television and videos, which defines a composite video signal with a refresh
rate of 60 half-frames (interlaced) per second. Each frame contains 525
lines and can contain 16 million different colors.
