Ok sorry about the below but I am struggling to explain.
My son is into drawing at the moment and also likes to copy pictures from magazines etc.
I remember years ago a tool which you could use to copy pictures.
It had a number of levered bits with two ends. One has a pen in the other a "fake" pen.
What you would do would trace the picture from the book using the fake pen and the other end would "copy" onto a piece of paper which was next to the drawing.
Apologies for random explaination above but I have googled loads of things but cant get any results.
Any help appreciated