I'll be teaching a workshop next weekend, Oct. 12-13, 2013, focusing on painting nocturnes. If you're interested in signing up for this unique experience, you can find more info here.
Ever since I began painting at night it's been a deep interest for me. It's not something that a lot of artists have attempted, and can be endlessly rewarding. Painting a moon rising over the horizon is great, but standing outdoors in the light of the full moon is magical, and it's not just black and white: the value range is reduced, but there is much more color than most would think. Try it sometime: just stand in the moonlight, and look at the color of say, the sidewalk versus the grass. Look at the trees and the sky. I'll bet you will start to see subtle differences that manifest themselves in color.
Nocturnes provide great situations to work with mood and quiet emotion, and the softness of shapes is infinitely fascinating: while individual shapes are distinguishable, it's hard to say where one thing stops and another begins. Therein lies the challenge of painting what you see, not what you know.
Painting at night is very similar to painting during the day as far as the approach to painting it and the materials required, with one crucial exception - a light. You need a source that provides enough balanced light to see what you're doing without being so bright that you can't see the landscape you're painting. I've come up with a solution that allows me to get very subtle color on location and is not a big surprise when I bring it indoors to a normally lighted room. Lighting and color will be discussed along with other issues one encounters at night in greater detail during the workshop.