Sometimes, in order to produce a realistic drawing the vanishing points need to be positioned beyond the edge of the paper. This is estimated perspective. When drawing, the guidelines they are projected back to imaginary vanishing points.
Estimated perspective allows objects to be drawn close up and yet still look as if drawn in perspective.

1. Select an everyday object to draw in single point perspective. The example seen here is a pencil sharpener.

2. Using a pencil draw a ‘faint’ cuboid in which the sharpener will fit. The cuboid is a frame and sets the limits of the basic measurements. Project guidelines to the imaginary vanishing points.

3. Add detail to the shape using a pencil. Again, draw the detail faintly.

4. Add further detail to the sharpener. Drawing faintly with a pencil ensures that mistakes can be corrected easily.

5. Use a fine ink pen to draw over the pencil lines. This makes the outline stand out.

6. Use a broad felt pen (brush type or chisel tip) to add colour to the sharpener. The colour should be the same as the colour of the fine ink pen used to draw the outline.