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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
ISOᲢInternational Organization for StandardizationᲣ; 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.
PAL
Phase Alternating Line (PAL) video format, primarily used in Europe, excluding
France, as well as Australia and parts of the Far East. PAL delivers 625 lines at 50
half-frames per second.
RAW
The RAW image format is the data as it comes directly from the image sensor of the
camera. No in-camera processing is performed before transferring the image to
computer.
Shutter Speed
The camera’s shutter opens for a length of time to control the amount of light that
reaches the imaging element. The length of time that shutter blinds are open
allowing light to strike the image sensor is called a shutter speed.
White Balance
The human eye and brain adapt to changes in lighting conditions, not only to intensity,
but also to the color characteristic of the light source, so that colors of the objects
look normal or accurate. For example, a white object will appear white whether it is
viewed under sunlight, tungsten or fluorescent illumination. However, color film or
digital camera must be adjusted, so that colors will be represented accurately, under
different types of illumination. This adjustment is called white balance. The function to
adjust a white balance automatically is called automatic white balance.
