I couldn't arrange the whole thing with one light source and a mirror next to a PC, so I did it in watercolours.
Took me a little more than 3 hours.
1. I noticed that mass light and shadow don't have to be equal in size, so to say - depending on light source, you can get lots of mass light or lots of shadow and very small areas of light. OK, maybe that was obvious.
2. Half tones in my case were much brighter than reflect light... I hope this is OK.
3. Highlights are not only the brightest part, but, on dark material (e.g. hair) are the places of the strongest contrast as well.
4. Reflect light gives you volume. Something I have heard lots of time, but really understood just now. With only light and shadow, the painting looks flat. With reflect light, it becomes three-dimensional.
5. Core shadow and mass shadow don't have to have distinct outlines - in my case, cast shadow from the nose blended with core shadow on the cheeck.
Hi McCloud, nice work on your portrait. Your image seems a bit too bright and your shadows too harsh. My suggestion would be to paint the face overall darker and save your whites for the brightest spots like maybe in the reflections in the eyes or on the tip of the nose. If you want to work in a high key where the skin seems really white try and make the shadows softer/brighter. The core shadow on your nose seems so dark compared to the core shadow on your cheek. Here is an image by Andrew Loomis as an example.
Notice how the values on the nose don't vary to much from the side of the face. It might help to work in graphite or charcoal if you want to work traditionally since it's easier to adjust values. Watercolor is really unforgiving.
Nice start. I love seeing these done in traditional media.
I think that your value range may be a little bit high key, and mostly keep an eye out for value transitions and gradients along the area where shadow meets light. If there is no transition and the value change is sharp and abrupt it suggests an edge like how a cube has a side and a front. The face is more spherical in its planar changes so the value transitions in the half tones will be more soft than you have here.
Keep up the good work. Some experimenting with achieving value gradients with this media will be a good exercise.