BRIGHTNESS The lightness or darkness of the image.
CHANNEL The component of an image.Your scanned image has three
channels: red, green, and blue (RGB).
CONTRAST The gradation of shades in an image. A high contrast image
has very dark areas and bright areas without many middle
shades. A low contrast image has many tones that are close to
the same brightness. Low contrast images are often described
as looking ‘flat’.
CROP To trim and delete the unwanted edges of the image.
DPI Dots (pixels) per inch.
EMULSION SIDE The side of the film coated with the photographic material.
GAMMA The contrast of only the middle tones.
HIGHLIGHTS The lighter areas of the image.
HISTOGRAM A graph showing the amount of each level of the 256
brightness levels.
INTERPOLATION A form of adding new pixels in an image when resampling up.
JPEG The JPEG (Joint Photographic Experts Group) compression
standard is capable of producing a high compression ratio
while maintaining image quality. JPEG is a widely supported
image file format.
MIDTONE The middle shades of an image, in between light and dark.
NEUTRAL Having no colour cast, such as black, white, or gray.
PICT (Macintosh operating system only) The PICT graphic file format
uses a lossless compression scheme and is compatible with
many Macintosh applications.
PIXEL Abbreviation for picture element. The dots that make up an
electronic image.
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GLOSSARY