Glossary, Continued
O (Continued)
ONSCREEN—An image that appears on the computer or television screen.
OPAQUE—(1) Impermeable to light; not transparent or translucent; (2) To
paint over unwanted portions of a negative with a solution to prevent light
from seeping through.
OPAQUE PROJECTOR—A device that projects an opaque object to a
desired size on another surface.
OPAQUE WATERCOLOR—See WATERCOLOR. A creamy, opaque
paint—like gouache or tempura, available in tubes, jars, or by mixing white
with transparent colors.
OPAQUING—Covering up with opaque paint.
OPTICAL CENTER—A point slightly above (10%) the geometric center of
a layout that the eye perceives as the center.
OPTICAL ILLUSION—An unreal or misleading image perceived by the eye
as real.
OPTICAL SPACING—The arrangement of spacing between letters for
legibility and appearance, which varies with the shape of the letters to
achieve optical equalization.
ORGANIZATION CHART—A block chart or diagram showing the names,
titles, departments, and responsibilities of personnel in an organization.
ORIGINAL —See MASTER. Copy submitted to the printer for
reproduction.
ORTHOGRAPHIC PROJECTION—A method of projection with six
principal views.
OSCILLATING AIRBRUSH—An airbrush with a reciprocating needle used
for fine detailed work.
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