The second major classification of parallel projections is orthographic
Orthographic projections are drawings where the projectors originating from
the observer or station point remain parallel to each other and perpendicular
to the plane of projection. For accurate and scientifically correct
presentations of objects, piping diagrams, machine, structural, architectural
drawings, and furniture design that can be sufficiently understood and
replicated by a craftsperson, use a form of orthographic projection.
Orthographic projections are commonly referred to as blueprints because the
method of reproduction, usually by the diazo process, renders the image with
a blue line. Orthographic projections are further subdivided into axonometric
projections and multiview projections.
Figure 6-12 shows an example of an orthographic projection.
Figure 6-12.An orthographic projection.
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