Da Vinci Notes 53 - Eye Can Never Be a True Judge

 

PERSPECTIVE.

 

Perspective comes in where judgment fails [as to the distance] in

objects which diminish. The eye can never be a true judge for

determining with exactitude how near one object is to another which

is equal to it [in size], if the top of that other is on the level

of the eye which sees them on that side, excepting by means of the

vertical plane which is the standard and guide of perspective.

 

Let _n_ be the eye, _e f_ the vertical plane above mentioned. Let

_a b c d_ be the three divisions, one below the other; if the lines

_a n_ and _c n_ are of a given length and the eye _n_ is in the centre,

then _a b_ will look as large as _b c. c d_ is lower and farther off

from _n_, therefore it will look smaller. And the same effect will

appear in the three divisions of a face when the eye of the painter

who is drawing it is on a level with the eye of the person he is