The structure above shows the NEW FOUNDATION for the exact perspective, which consists of an overlapping of two images: one out-of-focus image starting at the view point (where the viewer is located), and another clear image 17cm apart from the viewer, on the support line, where we will draw a flat surface that resulted from these two overlapped images.

Therefore:-

Work always with squares measuring 3x3 meters.

Scale: 1:50,

		3 meters correspond to............. 6 centimeters
		17 centimeters correspond to..... 3,4 millimeters
The depth point can be at the right or at the left of the vanishing point.