Sketchbook Tree and Degas

The above drawing from my sketchbook is what I would like to achieve more often.  Light in the shadows.  The media is hard charcoal pencil and fingers.  I did this one a couple days before Christmas.

I have been looking at and reading a lot about Degas lately (besides Cezanne).  Degas started the switch to pastel in the mid-late 1870's, and used predominantly all pastel from the 1880's on.  "...[H]e took full advantage of the different ways of handling pastel, sometimes drawing with the sticks, at other times creating tonal areas with a stump or with his fingers; often he worked with pastel and water, either wetting the stick or working the powdery pigment with brush and water to create fluid passages of color ...With pastel he was able to apply color in a linear manner, not so much to delineate form as to model it...the late pastels have a tonal substructure drawn by Degas the draftsman beneath their brilliant surfaces finished by Degas the colorist." (from Degas, Jean Sutherland Boggs.  The words above are by Gary Tinterow).