Vector Art Graphics
This is an interesting composite. Zoom out using your web browser and then compare the zoomed in picture. Shiny.
For all 15 pictures listed, read this article.
I first noticed that the skin tone was amazingly coherent, with the color of the eye shading and the hair matching quite well. I thought it was simply good makeup work and color coordination. But of course the colors would match, as an artist was responsible for choosing their specific shade in an environment that could be controlled better than natural colors and pigments.