Those of you who paint and have never tried tempera: it is high time you tried. It’s not a perfect medium but in my view, it beats acrylic paint quite easily and is probably cheaper if you paint large canvases and know where to buy your materials. The flip side is the same as with acrylics: if you let the tools dry, they’re gone. You’ll do quite well with tempera if you rinse your brushes every few minutes.
Tempera supplements both oil paints and watercolours: you can do the groundwork on paper with watercolours – the way I have done with the piece on this page – and continue with tempera – and do a bit more with watercolours – and then do a bit more with tempera again.
You can ground an oil painting with tempera. This was done frequently during the renaissance at least. The idea was to make a monochromatic painting with tempera and then dye it with oil paints. You can also just take a wood or plywood panel and use tempera as gesso, and then paint on it with oils. The feel of the support is far better than of one that has been grounded with regular gesso. It resembles the classic zinc white/calcium/glue/boiled linseed oil grounding (which is great as well).
Unlike acrylics, tempera stays “alive” at least for a few hours: you can wake it up with water. When all dry, it’s very durable. In fact it lasts hundreds of years – if not thousands – unless the support crumbles.
You can paint on almost anything with tempera: stone wall, paper, grounded canvas, wood panel, mdf, plywood…