Tips on Tempera

While I do occasionally work within traditional tempera painting guidelines, I also tend to ignore many of the fussier steps.

That being said, there are some things to remember when working with tempera. There are many reasons that oil painting became more popular.

1) Fat over lean: An ancient tradition, tempera painting has had centuries to reveal its limitations. Egg yolk is a fatty emulsion which works better if you put a fatty layer over a non-fatty layer, rather than the other way around. Working with distilled water and occasionally some egg white, I will sometimes lose track, and the leaner mixture will lift off the fatty layer below it, leaving streaks. Use it to your advantage if you want to lift off some small areas, but it doesn’t lift off evenly so don’t depend on it to erase mistakes.

2) Layering: Egg tempera does not offer the same textural advantages of oils or acrylics. The egg layers should be applied with thin layers to dry properly. It is RAW EGG after all, and will respond quickly to bacteria if it doesn’t dry well. Spread it too thickly and you will have some problems down the road with deterioration. Tradition states that you apply in crosshatching layers with a tiny brush, carefully working from darks to lights, layering opaque paints. I don’t insist on that, myself. I’ve worked with larger brushes, transparent paints and worked in lights and darks without a problem. But in thin layers. Don’t expect the rich brushstrokes and buttery goo of oils.

3) Drying time: Egg yolk dries to the touch quickly, very quickly. But it doesn’t completely cure for at least 10 days. Curing is also dependent on local humidity, which extends drying time. If new paint layers are added after the lower layer has cured, the new layers may NOT adhere properly, causing cracking and possibly peeling. So work steadily on a tempera painting, and don’t leave it unworked for more than 10 days, or there could be adhesion issues.
Icon writing tradition states that after a few layers are laid down, a thin wash of yolk and distilled water is worked over the layers to ‘unify’ them. This would help keep the layers damp and uncured until more work was done. I haven’t used this technique, so I haven’t experimented with the ratio of yolk to water.

4) Color issues: Egg yolk, sitting in the fridge, lasts only a few days – a week at most. Obviously, earlier artists had some issues with that, not having a way to keep the eggs cool, so the yolks went bad quickly. They came up with some methods to extend the life of the yolks. A few drops of vinegar or wine can change the acidity of the yolk, which keeps bacteria at bay longer. Be aware that the acidity can change the color of some pigments. Ultramarine blue is the most prominent example, losing most of its punch when the acidity rises. If you are using traditional dry pigments, you might need to do some research before working with the vinegar. I don’t usually use it. I just don’t process much egg yolk at one time, leaving it happily in the eggshell until I need some.

So, why use tempera instead of something else? It’s fussy, flat and messy.

First of all, the colors are unbelievable. Whether mixed with watercolor pigment or made from scratch with traditional or non-traditional dry pigments, the egg does things to colors that makes them glow.

Using crystalline pigments is a whole new experience. Azurite, Howelite, Malachite and well-processed Lapis Lazuli, as well as others, can form glittering pigments which do not translate well to linseed oil and are too heavy for suspension in watercolor medium. Pigment particles are larger and reflect the light like tiny gemstones.

Colors last. Properly applied, tempera paintings have lasted for centuries without dimming or cracking. No yellowing from oil or varnish. No water damage. After drying, tempera paint is permanent and resistant to dampness.

Fun factor: Nothing beats the feeling of crafting fine paintings using ancient techniques and choice materials. Ground gemstones, sun-warmed earth, dust, poisons, and dead bugs sit in all my tiny little jars, just waiting.

Nothing like it.

KJN

 


Eggs and toast (BI)

After a stretch of the flu, and a lack of energy due thereto, I have returned to my art.

Paintings are both transferred, silverpoint swan for DoL is proceeding apace, and I needed eggs this morning. And toast.

Having actually visited a large egg-laying facility, I am most often supportive of cage-free eggs. But it is the freshness of the eggs that really counts in painting, so sometimes I cannot be so choosy. When I can buy local eggs, I do. I can find out exactly when they were collected that way.

I suggest the following techniques for getting the freshest eggs when shopping at a grocery store. First, of course, check dates on the cartons for the freshest date. Then look at the eggs themselves.

Eggs that have been sitting around start to deteriorate and have a faintly speckled look, like clusters of light pinhole sized dots. I understand that this is due to some gases working their way out of the shell. Also, when held up to the light, a fresher egg has a very small air space at the end, while the air space gets bigger in older eggs. Get the best eggs you can get, freshness is more important than grade, though A and AA eggs usually have thicker whites and larger yolks, which is a good thing for our purposes.

Separate the yolks and whites, preferably with your hands. Egg separators and eggshells have sharp edges and may break the yolk. Much like making a meringue, you want to beat the egg whites to a foam, and not include any of the fatty yolk. After beating the egg whites to a good soft-peak foam, let them sit. Do not use any of the tricks of the baking trade in making egg whites form peaks, such as copper bowls or additional ingredients. Some of the traditional pigments will react chemically if given any incentive.

Oh, and make sure the eggs are room temperature. Cold egg whites won’t respond well to beating.

While waiting for the whites, take a whole, unbroken yolk, and roll it around a bit on a paper towel to dry it. Then hold it in your fingers and pierce the underside of it, letting the inner goo fall into a bowl. Discard the skin. If bits of skin get into the goo, fish them out with a fork. The yolk can be used straight from the bowl.

The whites will sit a while, and start to weep. At the bottom of the bowl, under the foam, a clear liquid will start to pool. Pour off this ‘glair’ and you have another binder for paint, with different properties than the yolk. Cover both ingredients with airtight covers, and they will last in the refrigerator for about a week. Take out a bit at a time for use, as the air will dry the ingredients quickly.

Yolk is a fatty emulsion that adds richness and depth to colors, and the yellow coloring does not change paint colors. If you use too much of it in a paint, the paint will look greasy and clumpy. Yolk is the favored part of the egg for paintmaking, because the added fat allows the paint to dry to a tough film that is resistant to water.

Glair has little fat and creates a matte finish. Used alone to make paint, it forms a more brittle, thin layer, which is more soluble in water. Some instructions for making tempera will state that only the yolk should be used, but experiment with the egg white glair and you’ll wonder why. The use of the glair creates more opportunities for texture changes, as glair is more soluble in water than yolk, and the paint moves and shines differently.

More details as we go.

And Panera bakery has the best cheese bread for making toast. Especially good with fresh, scrambled eggs on top.

KJN

 


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