We may think that all we need to know about the colors that we pick for our palette is that we like it or that it generally does pretty much what we want it to do.  We have already shown how dangerous that attitude may be especially if we are picking that beautiful pink for our flowers that just happens to be fugitive and will fade very soon as will Opera or Alizarin Crimson.

We may also get frustrated when we try to cover up a mistake with Hansa Yellow in watercolor or glaze using one of the Cadmiums in oil.  So lets learn a bit about TRANSPARENT and OPAQUE pigments.

All pigments in watercolor, acrylic, and oil are suspended in a medium whch may be more or less transparent, but the pigments themselves have those qualities as well.


If you are unsure of the transparency of a particular pigment there is an easy test.  Draw a heavy black line with a magic marker.  After the mark dries completely, paint a good layer of the pigment in question across it.  If the line can be seen easily, then the paint is transparent.  Light travels through the paint and then is reflected all the way back through it, giving us brilliant color.  If the line is just somewhat visible, that tells us that the pigment blocks the light from reflecting to some degree thereby blurring the image.  The paint or pigment is semi-opaque.  If you cannot see the line, then the pigment is opaque.  The light goes through the color but is not reflected.  The color is flat and blocks whatever might be below that layer of paint.sunflowers I copy

If you want to glaze, let your colors mix by putting them on top of each other, you MUST use transparent pigments.  Opaques are used when you want to cover the lower layers or perhaps fill the area in one coat.  In some instances you may add additional medium to a semi-opaque pigment to get a passible transparent, but for best results learn which pigments are which and use them to their best advantage–the transparents for those beautiful clear tones and the opaques when you need those strong powerful brights and lights.  Most every painting will need some of each.

A ready reference for Transparents and Opaques

Blues                                                     Reds

French Ultramarine – T                      Alizarin Crimson (Perm) – T

Prussian – T                                         Quinacridone  Crimson, Magenta – T

Pthalo Blue – T                                    Cadmium Reds – O

Cerulean – O


Hansa Yellow (WC) – T

Winsor Yellow – T

Cadmium Yellow – O

Indian Yellow – T

Note:  Colors vary from company to company as do their degree of transparency.