"There is a difference between good and bad reference. When I say “good” reference, I really mean “useful”. The number one quality of a useful reference image is the light. The light should be simple with a single, dominant light source being the preferred scenario. This type of lighting (which is also ideal for life drawing models in studio) is what produces the clearest light and shadow patterns and a clear distinction, or border, between light and shadow. It’s this clarity that is vital when studying figure drawing, head drawing & painting. This is especially important for beginners, young artists and artists in training.
Good reference is important for a many reasons. As an artist and educator, I value good reference simply because figure drawing is hard. Yes, figure drawing is hard, and since it is hard, it’s best to choose reference and lighting scenarios that can help simplify the drawing process and smooth out the learning curve. Why fight and struggle and swim upstream? Get good reference and lighting which will help you get the skills."