Orthographic projection can be described as a method of representing three-dimensional objects, usually by three two-dimensional drawings in each of which the object is viewed along parallel lines that are perpendicular to the plane of the drawing.
Oblique projection is a simple type of technical drawing of graphical projection used for producing two-dimensional images of three-dimensional objects in which the projection lines are not orthogonal to the projection line.
In both oblique projection and orthographic projection, parallel lines of the source object produce parallel lines in the projected image. The projectors in oblique projection intersect the projection plane at an oblique angle to produce the projected image, as opposed to the perpendicular angle used in orthographic projection.
What You Need To Know About Orthographic Projection
- Orthographic projection is a method of projection in which an object is depicted using parallel lines to project its outline on a plane. For example, an orthographic projection of a house typically consists of a top view or plan and a front view and one side view (front and side elevations).
- Orthographic projection can also be described as a two-dimensional graphic representation of an object in which the projecting lines are at right angles to the plane of the projection.
- Orthographic projection can also be referred to as orthogonal projection.
- It is a form of parallel projection
- In orthographic projection, the projector lines intersect the plane being projected on to at a perpendicular angle (thus, they are orthogonal).
- Typically, an orthographic projection drawing consists of three different views: a front view, a top view and a side view. Other names for these views are plan, elevation and section. Occasionally, more views are used for clarity. The side view is usually the right side, but if the left side is used, it is noted in the drawing.
- Orthographic projection can be subdivided into three categories: isometric, diametric and trimetric projection.
- An orthographic drawing is a clear, detailed way to represent the image of an object. It may be used by engineers, designers, architects and technical artists to help a manufacturer understand the specifics of a product that needs to be created.
- A lens providing an orthographic projection is referred to as an object-space telecentric lens.
- When principal planes or axes of an object are not parallel within the projection plane, but are rather tilted to reveal multiple sides of the object, the projection is referred to as axonometric projection.
What You Need To Know About Oblique Projection
- Oblique projection is a simple type of technical drawing of graphical projection used for producing two-dimensional images of three-dimensional objects.
- Oblique projection can also be described as a parallel projection in which the projection lines are not orthogonal to the projection line.
- Oblique projection is a form of parallel projection.
- Usually, the presence of one or more 90^{o }angles within a pictorial image is usually a good indication that the perspective is oblique.
- In oblique projection, the projector lines form oblique angles (non-right angles) with the projection plane.
- There are two types of oblique projections: Cavalier and Cabinet. The Cavelier projection makes 45^{o} angle with projection plane whereas In Cabinet projection, the projection of a line perpendicular to the view plane has the same length as the line itself.
- Usually when drawing, all the three axes of the oblique drawing are constructed in which one axis is horizontal and the other is vertical while the third axis is from 30^{o} to 60^{o} to the horizontal line. At least two views of orthographic projection are selected.
- Oblique projection is commonly used in technical drawing.
- Oblique drawings are also used in engineering and design. The object is drawn with the most distinguishing features facing towards the observer, showing true shape of these features.
Also Read: Difference Between Parallel And Perspective Projection
Difference Between Orthographic And Oblique Projection In Tabular Form
BASIS OF COMPARISON | ORTHOGRAPHIC PROJECTION | OBLIQUE PROJECTION |
Description | Orthographic projection can also be described as a two-dimensional graphic representation of an object in which the projecting lines are at right angles to the plane of the projection. | Oblique projection can also be described as a parallel projection in which the projection lines are not orthogonal to the projection line. |
Form | It is a form of parallel projection | Oblique projection is a form of parallel projection. |
Types | Isometric Projection Diametric Projection Trimetric projection | Cavalier Projection Cabinet Projection |
Projector Lines | The projector lines intersect the plane being projected on to at a perpendicular angle (thus, they are orthogonal). | The projector lines form oblique angles (non-right angles) with the projection plane. |
Application | Used by engineers, designers, architects and technical artists. | Commonly used in technical drawing. |