Question

Why do illustration artists use colored pencils like red and blue to draw the sketch? How is it helpful?plzz answer!!!

Answer 1

Answer:

Non-photo blue (or non-repro blue) is a common tool used in the graphic design and print industry. It is a particular shade of blue that can not be detected by Graphic Arts Cameras or copiers. This allows artists to lay down sketch lines without the need to erase after inking

Sketching with red chalk called 'conte' is used as an under drawing and if just used as a drawing you have to spray with a 'fixative' a clear spray that will protect the chalk from coming off.