109. cast shadow vs form shadow

everything we perceive with our eyes can be broken down into values of light and dark.

this is a big part of drawing and painting - trying to capture the interplay of light and shadow. When I’m using a pencil, all I can really do is darken things on a white piece of paper so I need to really focus on how shadows move across a form.

Today I was watching a last night video about portrait painting, and he mentioned the “form” and “cast” shadows

cast shadows are what you would think of as a shadow, it’s the one that follows you around as you walk. When your body gets in the way of a light source, it creates a road block in the lights path. Like a cookie cutter, your silhouette is sliced out and a shadow is cast. Cast shadows are usually crisp and clear, especially close to the subject, like where your feet meet the ground. From here at gently fades to be less clear and less dark the further it gets from your body this is because other light sources are cut in and reflecting, and fading to make that shadow dissipate.

Form shadows are different - picture of basketball in the sun. as the light wrapped around the sphere, it slowly fades to be darker and darker. As I’ve been learning to draw realistically I’m coming to realize how important these form shadows are for how we perceive shapes.

Fascinatingly, the saturation of the basketball will be strongest at the point where light and shadow meet.

For more check out this lovely video:

https://youtu.be/qKKjJPbcE1E?si=CWQw08zJl3tSyV_w