Portrait Trial, part 1

While I'm loving doing still-lifes, I keep reading about the Masters - Rembrandt, Vermeer, and one of my favorites, John Singer Sargent.  Is it any wonder then, that I'm curious if I can paint a figurative or a portrait?

I know most people don't have 3 hours periods to sit for a portrait each day.  So I'm going from a photograph taken of my father-in-law (it seemed the most portrait-like position).

It's only in the rough stages, but so far, I'm liking my progress.  The skin tones are a challenge!  I think, when I'm done with this, the skin of a tomato or pear or apple will be easy by comparison!