ART DIGRESSION: Oils vs Acrylics
Acrylics have their own properties. They're a recently invented paint-in the 1950's they came into being. The make-up of them is basically 15% color mixed with 85% acrylic resin-more or less a more fluid form of Elmer's Glue. It's why they dry fast and, yet, the color never seems as rich as it could be, especially after they dry. Acrylics dry in the air, fast and their make-up changes which is why there is such a huge color shift sometimes. Acrylics can be mixed with water or run through an airbrush. You can "draw" with acrylics if the brush is fine and you make a thin mixture of paint. But because they're inherently "plastic" they tend to look a bit plasticy and also flat when dry. You can fake oil-paint effects and, most store bought/tubed acrylics are designed to emulate just that. Varying brands of them mean also the quality varies. It's also alot harder to work from dark to light with acrylics. Acrylics are good for wash effects and can be thinned to use like watercolors and unlike watercolors, they set up in thin layers one on top of another.
Oils are simply put, alot sexier to use. Oils are close to 85% pigments mixed with linseed oil or recently, safflower oil. I've found some of the cheapest brands, the better because they use linseed oil. The more expensive have supplanted this with safflower oil which can have problems if it's exposed to too much heat-it melts off. Oils are mixed with linseed oil or other mixtures of such and set up with the idea that light penetrates them and reflects back, giving an oil painting it's obvious brightness and depth. Oils on canvas have a nice tactile feel. Moreso than acrylics on canvas. You can do alot of what we call "glazing" with oils-building up thin layers on top of thicker ones, and it just gives the painting more and more depth. An oil painting can be left for the night and when I return in the morning, I still have the same color values and depth than I would with acrylics. When I went over to oils, I realized all I was missing since I last worked with them in school in the late 70's. Oils can take a long time to dry however! This prompts me, especially for commercial jobs, to use Galkyd or Liquin. Galkyd is a resin medium that promotes fast drying. Galkyd resin is what is in Alkyd paints-Alkyds are Oil's related cousin and they are fast drying but, can be chalky, I'm told. However Galkyd in oil paint is the best of both worlds.
I think both types of paint-Acrylics and Oils- have their own properties and uses. It's just lately, oils seem a whole lot more fun and satisfying.