New (old) trick ...

Frustrated with errors of perspective I came across this trick that I had seen previously but never tried.

So simple and so easy !

A bulldog clip and a length of elasticated 'string' 
Clip the string on the 'eye level' line and swing it up and down to give you the correct angles for the perspective !

This quick sketch looks so much better , now to try fixing 2 point perspective!

Alan