This Mind-Blowing Timelapse Drawing Of Robin Williams Was Done By A 21-Year-Old.
Heather Rooney is a 21 year old art student who is a master of using Prismacolor pencils to create photorealistic drawings. You can check out her website for tons more of her amazing artwork.
Here are some other action shots that show you how she works.
I went through a phrase of photorealism in my drawing, and it is very, very challenging. I definitely admire this level of skill, especially at a younger age.
Source: Heather Rooney