This is another big one- about 3′ by 5′. The red background really sets off the green Humvee. Red and green are complimentary, but I needed to change the value as well- the light green contrasts with the darkness of the red. Otherwise, it can be muddy when you squint. Which reminds me, three good rules for evaluating your process:
1. SQUINT!! Your contrast, or lack of, will be evident.
2. Look at your art upside down or in a mirror. Especially good with portraits or anything with perspective.
3. Take a picture of your art, then load it up and change it to b&w. Contrast and detail that need work are more obvious.