View Full Version : is gouache and opaque water color the same thing?

05-16-2013, 11:44 AM
Hello, I'm looking into gouache at Dick Blick and see in the description of some that gouache is opaque watercolor. Is that right?
Also, arae the primary colors the same in gouache the same as in oils--Thalo Blue PB15, Rose, PV19, and cad yellow, PY 35?

05-17-2013, 12:08 PM
Both gouache and watercolor are water medium paints. Gouache is opaque, whereas watercolors have some opaque, some semi opaque, and some transparent pigments.
The range of hues in gouache is much greater than the range of hues in watercolor because gouache is used by illustrators for artwork that will be scanned for publication, and permanence is not a requirement for that type of art work. You should be able to get all watercolor pigments in gouache, but not vice versa, as watercolor is use primarily for permanent art. Top companies label tubes with permanence ratings of pigments used in both mediums.
If the tubes in any medium are labelled PB 15, Pv 19, and PY 35, the pigments are the same. However, you will see slight differences between mediums and manufacturers, even with identical pigment identicafation numbers.

05-19-2013, 06:30 AM
Although it is generally true that gouache is opaque, some manufacturers have transparent paints as well. An example is M. Graham.

There are two ways of making gouache - one way emphasises opacity, while the other emphasises high pigment load. In the first case, the paint includes an opaque filler like chalk or a substance similarly opaque in water; in the second case the opacity is achieved by pigment type and formulation.

In general gouache paints are "coarser" than watercolour, for want of a better description. The dispersion and milling of gouache pigments does not need to be as fine as in watercolour, but this is relative. Gouache is generally less active wet in wet because of the differences in formulation, and is expected mostly to be used with less water.

Because overpainting in layers is common with gouache, the paint is formulated to be somewhat less easily soluble once dry.

Where a manufacturer has kept the transparent nature of the pigment, as for example PV19 or PB15, it can of course be made opaque with white. In that sense it is then used in a manner similar to oils or acrylic.

06-28-2013, 02:43 PM
Thanks--even though a bit late.
The information has been helpful.

08-12-2013, 11:57 PM
The short answer is yes. They are not only both water based, but they usually use the same kind of binder (often gum arabic). Chemically there is little difference between watercolor and traditional gouache*, and they can be intermixed easily, but manufacturers usually emphasize opacity in gouache and transparency in watercolor.

*unlike acrylic gouache or the similar casein paints, traditional gouache can be re-wetted with water

Phil Coleman
11-12-2013, 03:24 PM
Some brands stipulate that they achieve their opacity as a result of a high pigment load rather than by using filler. I know Winsor and Newton stipulate this but do other brand make the same claim also?