My interest in trying a large format portrait came from reading (and thoroughly enjoying) Mary Whyte's Painting Portraits and Figures in Watercolor (http://amzn.com/0823026736). Her amazing paintings have the rare quality of capturing both the likeness and the life history of the subjects.
The paper I used for my parents portrait was 22 x 30 inch Arches 140 lb cold press paper, stretched and stapled onto a wooden board. The watercolors (tubes and pans) used in this painting were primarily the following (Winsor and Newton):
- French Ultramarine
- Permanent Rose
- Raw Sienna
- Vandyke Brown
- Hooker's Green
- Lamp Black
- Cadmium Orange
- New Gamboge
- Zinc White (Gouache)
- Davy's Gray