this illustration is an excellent tutorial to explane clearly some important rules about car sketch 3/4 view perspective.
The little doodle at the bottom of the drawing shows the type of perspective and vanishing points position, next we have a center line (Y0) and also the wheels ellipses having the minor axes pointing to the vanishing point.
The side view sketch on top left corner shows proportions using the wheel and this will help to set up the perspective too, in fact we take the rear wheel and create the same space with the front one using the rear wheel (ellipse because it is in perspective).
Study this one because it is a very good help for all even for myself, enjoy!
-2006-2012 Http://lucianobove.blogspot.com All Rights Reserved