Egg Tempera: Yolk, Thin Layers, a Firm Panel
How egg tempera binds pigment with yolk, why it suits thin layered strokes, and what oil painting later made easier.
Egg tempera is paint made by binding pigment with egg yolk, thinned with water. For centuries it was a normal way to paint panels in Europe, especially for work that needed a clear, fine surface. Oil paint did not appear overnight and delete it. Oil gradually offered different virtues: richer darks, softer blending, a more flexible film. Tempera remained the method of thin, deliberate layers. Knowing that difference stops you from judging a tempera picture as a failed attempt to look oily.
What the yolk changes
Yolk dries quickly to a lean, tough film. You cannot push a passage around for an hour the way Alla Prima: Finishing an Oil Study in One Sitting expects. Strokes stay. Modelling is often built from many small hatches, light over dark, rather than from a blended smear. The surface can look luminous because the layers are thin and the ground is often bright.
The binder is ordinary and it is also perishable in the pot. A mixed cup does not keep like a tube. Historically, painters mixed what they needed. If you try the medium, use fresh yolk, keep the tools clean, and do not store a jar of experiment until it smells. This is a material with a kitchen origin, not a casual acrylic.
Panels, not floppy cloth
Tempera wants a firm support, traditionally a prepared wood panel. A flexible canvas moves, and a brittle film is unhappy on it. The ground was smooth so fine lines could sit without catching. That is a different appetite from heavy oil on a woven texture. Canvas, Board or Paper? is the modern choice. A rigid board is the heir of the panel if you are merely curious.
Gilding and tempera often shared a picture. Gold leaf is not paint, and it does not behave like a yellow. The flat light of gold beside the modelled face is part of the look of many old panels. You can notice it without trying to imitate a shrine.
What oil made easier, and what it lost
Oil allowed softer transitions and deeper darks, and it let painters rework a wet passage. Glazing for Luminous Colour inherits the patience of thin layers and spends it in a slower binder. Underpainting: A Quiet Start for Stronger Oils is a cousin of the tempera habit of settling the forms before the last colour.
What oil can lose is the crisp, linear light of a stroke that dried before you could fuss. Tempera's limit is a discipline. You place a light and leave it. If you want that discipline without yolk, a small gouache study on a firm board will teach the same restraint more safely than a half-understood egg recipe.
Looking, not reviving a guild
When you see a tempera panel, look for the hatch, the brightness of the ground, and the absence of oily blur. Do not expect the recipe from a short article to make you a panel painter. Recipes vary, grounds matter, and a badly prepared board will warp or flake whatever the history.
Borrow the looking. Paint one study in small, unblended strokes on a rigid surface and stop when the form reads. The medium's history is a history of patience and support. Both are available in the room you already work in.
Frequently asked questions
Is tempera the same as poster paint? No. School poster paint is a different, opaque water-based paint. Egg tempera is pigment in yolk. The words meet in a classroom and part in the studio.
Can I put oil over tempera? Painters have done so on sound panels, lean tempera underneath and oil on top. It is not a beginner experiment on a flexible canvas. If you are unsure of the board and the binder, keep the study in one medium.
Why does tempera look bright? Thin layers over a pale ground, and very little muddy blending. The brightness is structural. A dark, oily varnish on top of a reproduction is a different object from the panel.