Copying by picture is a bit more convenient because I don't have to pay attention to lights and angle changes, so, to do these speed drawing videos (without moving the sheet and without interruption), I prefer copying by pictures . You can find here a drawing copy from life: [link]
thank you I spent twenty years drawing and twenty years without touching a pencil I started drawing as a child, I attended the Art School and the School of Applied Arts, then I worked a couple o f years as ads/editorial illustrator and painter. I quit drawing when I was 22. I graduated in Architecture just doing some technical drawings for a few years. I start drawing by hand again three months ago after 20 years.