What Is The Purpose of Medium?

I know that I am suppose to use mediums in white, clear and black for wet on wet. I got that. But what is the difference between Medium and the Medium white, clear and black? Does the medium just give the paint a transparent effect? Is that what it is for? Or are they the same?

Jayne,

Everything you’ve mentioned is a medium.

Mediums in white, black and clear are mediums put out by the Bob Ross Company, Alexander Company and others. They are especially formulated to keep the paints wet so that someone can finish a painting in one session.

Whereas the common thought is that wet-on-wet, or wet-in-wet by definition means a painting must be finished in a single sitting, is not necessarily correct. Whereas many of us do finish a painting in a single setting, wet-on-wet, is simply a matter of layering paint on top of paint while its still wet. So wet-on-wet isn’t necessarily restricted to oils. Newer acrylics will allow this to happen and I’m experimenting with some right now.

Mediums has a few jobs, the most common one is to allow the paints to flow smoothly onto the painting surface (canvas). If you’ve ever tried to just take oil or acrylics and apply directly to the canvas, you’ll understand what I mean.

In general, medium’s purposes include:

  1. Allow paints to flow smoothly onto the canvas
  2. Keeping the canvas wet
  3. Facilitate the blending of colors
  4. When tinted with color, will permeate this color throughout the entire canvas
  5. Allowing the paints to dry either shinny, dull, flat, glossy, etc….
  6. Build structure or relief with paints
  7. Allow faster drying i.e. Archival Lean Medium

But the two primary purposes are to allow the paint to flow smoothly onto the canvas and to keep the canvas wet during the immediate painting session.

Darrell