I copied a small sample of a full illustration from one of Bernie Wrightson's Frankenstein pieces. This is the exercise from Lesson 14.

The top three things that stood out for me about this piece were:

1. Continuous lines to express tonal values
2. Missing edges, using the background to complete the shapes
3. How the master rendered the light reflected from the window (the window is cropped out in this sample, but notice the diagonal strokes below the bookshelf support beam on the right side of the picture plane)

Learning reflections:

I learned to trust the process. Master Wrightson builds his pieces in layers, which makes it challenging to “see” good results until the sample is complete.

Some of the elements in the picture plane take form only after the background is fully rendered.

Doing studies like this one has taught me to:

1. Plan the values
2. Map out in pencil where the tonal transitions will go
3. Do the outlines last

The master's sample:

My study: