I just realized that my dealer has large color swatches in this giant brochure-like display, not to be confused with the brochures they give away, which also has color swatches. The swatches in the regular brochure are small (apx. 1/2 inch by 2 inches) but the swatches in the big display are about 2 inches by 2 inches or so. This will be much better than what any photograph can reproduce.
So go by your dealer, pick up a brochure and check out the large display book. That should help but, of course, it's not like seeing the actual car in the color.