These compositions are no larger than 2" x 2-1/4". The comps show their relative size to one another.
Doing black and white composition allows me to understand the relative values, identify the best composition and potential problems in placement and size of the main elements. If the values are placed accurately, It also gives me an idea of the particular "light" of the landscape.
Gouache and Tempera, unpretentious as they are, are a very sophisticated media, capable of very fine detail. They also are a good stepping-stone toward learning to paint with oils.