Realistic Art in Egg Tempera
Making the paint
 

All Paint Starts as Powder Pigment

No matter which medium you choose to work with, if it's got color, it started out as pigment powder.  Michelangelo had a lot more limitations than we do today (modern pigments are, after all, already powder when we get them, and man made organic compounds give us a much wider variety of colors to choose from), but the process is still the same.

Pigment powder + binding agent + plus thinning agent = paint.

And while modern painters have a myriad of colors to choose from unavailable in Michel's time, starting with a limited palette is a good idea. Think of the basic color wheel, and purchase colors that fill that need: red, yellow, blue, orange, purple, green, white, black and brown. You can get them at most professional artists supply stores, or look for them on line by searching for "pigment powders" or "artists ground pigments" or some such category.

Simply put a small amount of the paste in the well of a good watercolor palette, add the medium in a roughly 3-2 proportion of medium to paste, and mix. Though a hard plastic tool is recommended as a mixing tool, nothing is actually made for this purpose, so search your art supply store for anything suitable.  (I like a plastic item made for rubbing transfer letters like Chartpak onto paper, which you can find it in the graphic arts sections of you art store, but you may find something you like better.)  It should be about pencil sized and made of plastic so the different pigments will clean off easily without staining or sticking to the tool.'

The final mixture should have a thick, creamy consistency, no where nearly a thick as oils or acrylics, and should handle easily with a fine watercolor brush. There is no formula. If there is too much paste, the paint will appear thick and chalky; if too much medium, it will be too thin and streaky. And since different pigments handle differently, the final decision is up to you.

The Painting Surface

You are now ready to paint.

The egg yolk binder makes the paint dry really fast (30 -60 seconds), but this also means that it's a thin, brittle paint, without the elasticity of oil or acrylic paints. The painting surface needs to be hard and smooth so the brush strokes will be clean and crisp, and won't flake off if the surface flexes, as it would with canvas or paper.  A plaster wall would be ideal, but they're a little hard to haul around, and highly polished wooden panels are a lot of work to create and can be fairly expensive. Fortunately, modern materials have given us an ideal working surface...Masonite!   It's cheap, lightweight, plentiful, and acid free.