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Perspective is a geometric method of representing on paper the way that objects appear in real life i.e. they get smaller and closer together the further away they are from the eye of an observer. It is the most realistic of all pictorial drawings It is is the way real threedimensional objects are pictured in a photograph that has a twodimensional plane Perspective or central projection is used in creative art or technical sketching but seldom in technical drawing
Lecture 5 Thursday 27 November 2014 1 ENGINEERING GRAPHICS 1E9 Lecture 5: Perspective Lecture 5 Thursday 27 November 2014 2 Perspective/Central projection • Perspective is a geometric method of representing on paper the way that objects appear in real life i.e. they get smaller and closer together the further away they are from the eye of an observer. • It is the most realistic of all pictorial drawings • It is is the way real three-dimensional objects are pictured in a photograph that has a two-dimensional plane • Perspective or central projection is used in creative art or technical sketching but seldom in technical drawing Lecture 5 Thursday 27 November 2014 3 Projectors or line of sights are not parallel to each other Lecture 5 Thursday 27 November 2014 4 Pictorial drawings Perspective drawings differ from other types of pictorial drawings. In Isometric, Dimetric, and Trimetric drawings, the lines remain parallel and never converge at a single point. They are useful for conveying technical information but lack the quality of realism when compared to the perspective view. Lecture 5 Thursday 27 November 2014 5 Perspective System MAIN ELEMENTS 1. The observer’s eye 2. The object 3. The plane of projection 4. Line of sight Lecture 5 Thursday 27 November 2014 6 Perspective System • Observer’s eye is station point SP and the visual rays are the line of sights • Picture plane is the plane of projection or the paper • Visual ray at eye level marks horizon on picture plane Lecture 5 Thursday 27 November 2014 7 Perspective System Lecture 5 Thursday 27 November 2014 8 Vanishing Point • The lines parallel to each other but not parallel to the picture plane converge towards a single point on the horizon - VANISHING POINT Lecture 5 Thursday 27 November 2014 9 Notes • Observer’s eye is station point SP • Visual ray at eye level marks horizon on picture plane. The horizon line (HL) is the position of horizon. • The central line of sight should direct towards the centre of interest. • The location of the picture plane (PP) determines the size of the object on the PP. Moving the PP alters perspective or scale but not proportion. • The lines parallel to each other but not parallel to the PP (horizontal lines) converge towards a single point on the horizon - Vanishing points (VP) • The ground line (GL) represents the edge of ground plane on which object rests. GL defines the lower limit of drawing. Lecture 5 Thursday 27 November 2014 10 Perspectives [...]... 27 November 2014 Types of Perspective • 1-point perspective/ Parallel perspective • 2-point perspective/ Angular perspective • 3-point perspective 11 Lecture 5 Thursday 27 November 2014 One-point Perspective 12 Lecture 5 Thursday 27 November 2014 One-point Perspective • One face of object is parallel to picture plane, one VP 13 Lecture 5 Thursday 27 November 2014 Two-point Perspective 14 Lecture 5 Thursday... November 2014 Perspective of a rug 26 Lecture 5 Thursday 27 November 2014 Perspective of a door 27 Lecture 5 Thursday 27 November 2014 Perspective of a window 28 Lecture 5 Thursday 27 November 2014 29 2-Point perspective drawing we are going to create a 2 Point Perspective view drawing of our subject working from plan and elevation view STEP 1 Lecture 5 Thursday 27 November 2014 30 2-Point perspective. .. Two-point Perspective • Object at angle with picture plane, but vertical edges are parallel to picture plane, two VP 15 Lecture 5 Thursday 27 November 2014 Three-point Perspective 16 Lecture 5 Thursday 27 November 2014 Three-point Perspective • No system of parallel edges with picture plane, three VP 17 Lecture 5 Thursday 27 November 2014 18 1-point perspective drawing (1) A simple one-point perspective. .. 2014 23 1-point perspective drawing(6) Step 9 From the corners of the front view (D, E, G and F), draw visual rays to VP Lecture 5 Thursday 27 November 2014 24 1-point perspective drawing(7) Step 10 The line from point A of the plan view to SP intersects the PP at point H Draw a perpendicular line from H to intersect the visual rays (points J and K) Lecture 5 Thursday 27 November 2014 25 Perspective of... Lecture 5 Thursday 27 November 2014 19 1-point perspective drawing(2) Step 3 Draw the plan view above or below the PP (easier to draw it resting on top of PP) Lecture 5 Thursday 27 November 2014 20 1-point perspective drawing(3) Step 4 Draw the ground line (GL) in an arbitrary location below and parallel to the PP Lecture 5 Thursday 27 November 2014 21 1-point perspective drawing(4) Step 5 Locate the station... of the plan view (SP may also be placed 2 or 3 times the object’s greatest length from the nearest point of the plan view but if placed any closer, distortion of the perspective will result.) Lecture 5 Thursday 27 November 2014 22 1-point perspective drawing(5) Step 6 Project the width of the plan view to the GL Step 7 Draw the elevation of the object on GL If the plan view of the object is touching... The first line to draw will be the Picture Plane Lecture 5 Thursday 27 November 2014 31 2-Point perspective drawing STEP 3 Place the lower right corner of Plan View on the PP and rotate it clockwise The choice of 30° is arbitrary, but should provide a good view Lecture 5 Thursday 27 November 2014 32 2-Point perspective drawing STEP 4 In Fig 4 we will locate the Station Point Measure the horizontal width... Picture Plane downward At two times X we will locate the Station Point Lecture 5 Thursday 27 November 2014 33 2-Point perspective drawing STEP 5 Draw lines for the Horizon and Ground Line Fig 5 The location of these lines are infinitely variable Lecture 5 Thursday 27 November 2014 34 2-Point perspective drawing STEP 6 Draw 2 lines from the SP that are parallel to the bottom edges of the Plan View Fig 6... located Lecture 5 Thursday 27 November 2014 35 2-Point perspective drawing STEP 7 The last part of preliminary layout will be to place the Side Elevation view from Fig 1 onto the GL Project a line (orange dashed line b) from the top of the Elevation View to the vertical Line Of Sight (LS) Fig 7 Lecture 5 Thursday 27 November 2014 36 2-Point perspective drawing STEP 8 We are now ready to start projecting . November 2014 10 Perspectives Lecture 5 Thursday 27 November 2014 11 Types of Perspective • 1-point perspective/ Parallel perspective • 2-point perspective/ Angular perspective • 3-point perspective Lecture. 27 November 2014 1 ENGINEERING GRAPHICS 1E9 Lecture 5: Perspective Lecture 5 Thursday 27 November 2014 2 Perspective/ Central projection • Perspective is a geometric method of representing on paper. 12 One-point Perspective Lecture 5 Thursday 27 November 2014 13 One-point Perspective • One face of object is parallel to picture plane, one VP Lecture 5 Thursday 27 November 2014 14 Two-point Perspective Lecture