Pigments

Maurizio Spatafora

Retouching Color Theory

• With retouching there are two approaches: – Additive (varnish colors) adding up transparent

glazes– Subtractive (gouache base colors)

• Remember that light absorbs colors, we see what is reflected back.

• When mixing , keep in mind we are subtracting certain colors from light.

• When applying the gouache, the colors are mixed; the varnish colors are added as straight colors.

• Red and Blues become lighter over time.• Earth colors become more transparent over time. • Always respect the perimeter of the loss; stay within

the lacuna.

• We are grinding pigments to make a retouching palette. • The palettes start with white and finish with black, though

the colors aren’t in a normal order.• The pigment is ground on frosted glass. Each pigment

needs a different amount of grinding time. Refer to the pigment palette reference sheet for times.

• Grinding is done with distilled water and a glass pestle. Once the pigment begins to thicken, add more water. Scrape the pigment to the center and repeat the process.

• There are more detailed directions on the reference sheet.

Making the Pasticche• Pasticche are “pills” of paint. They are made by mixing

the ground pigment with a 50/50 mix of Canadian Balsam and Mastic Varnish. These pasticche are to be used for the final varnish glazes to simulate antique colors. – Why these two varnishes? They equal each other out. Mastic

Varnish yellows and is very flexible. Canadian Balsam is more rigid, so the two are mixed together.

• To mix the varnish and pigment together, add a little of each at a time and mix with a palette knife until all is mixed. This should be done on a smooth glass surface. Each pigment will absorb a different amount of varnish. Earth colors absorb more, so more varnish will be needed for these colors.

• To produce a pasticche on the palette, gather some pigment on the tip of the knife and tap it on the palette and gently pull and twirl the pigment away like soft serve ice cream. Once done with the palette, place it in a dust free area.