Searching for that magical medium that will solve all of our painting problems is a brief (sadly for some, not so brief) spell that many artists fall under.
Eventually the realisation sets in that no matter how close we get to the mediums used by the old masters, it won’t help if we cannot draw or paint. But that’s another story.
Knowing the technical side to painting certainly comes in handy though, and will prevent disappointing effects on otherwise successful or cherished paintings.
Things like sinking in or a dulling effect, or even a cracking of the paint film.
The medium used by the baroque painters, notably Rubens, was as follows - at least according to experts in the field. I use this medium for my own studio pieces.
Ingredients for Base Medium: 3:2:1.
Venice Turpentine. 3 Parts.
(from the Larch tree and NOT a solvent but a honey like resin) You can get it in a tack shop for MUCH less money, but it may have impurities and not be as refined as the artists grade, although I have not been able to notice much difference.
Stand Oil (essentially sun thickened Linseed) 2 Parts.
Damar Varnish (to speed up drying) 1 Part.
Thixotropic Base Medium.
A mixture of these three forms a Base Medium which is thixotropic (requires agitating for it to become more fluid) in nature and acts to suspend the pigment, retaining its qualities long after drying. The drying process is a hardening through oxidation, forming a resilient protective coating.
The Base Medium should not be used neat otherwise an unwelcome wrinkling effect will result from too much oil content.
Instead, this base should be mixed in varying degrees, with artist grade turpentine.
For example, if you are painting in layers, in the Flemish style, you might have the following:
Gum Turpentine : Base Medium ratios:
4:1 for underpainting layer
3:1 for adding the bright areas
2:1 for the Abozzo (dead colouring)
1:1 for the final colour layer.
These steps can be further stretched by adding a small drop of stand oil to each.
Artists that have an intolerance to turpentine can use citrus oil or odourless spirits instead.
Your medium in this case would be: Turpentine : Stand Oil in the same steps as above.
Drying times will be slower, however.
Golden Rule. Fat Over Lean.
Whatever medium you use, If painting in layers, it is imperative that the fat over lean rule is observed.
Hence the reason for the first layers (under-painting) having a higher proportion of Gum Turpentine as it will thin out the Base Medium (make it leaner) and as you add more layers, with drying in between, the Base Medium increases in proportion to the turpentine (making it fatter).
This way, earlier layers dry much sooner than the top layers, preventing cracking.
Adding a very light wash of the medium to the area that you are working before painting will help prevent the paint from sinking in and looking dull. Don't over do it though. Brush a small amount on with a bright and gently wipe with a clean cloth.
Mixing a small amount of your medium to your paint mixtures will also help to suspend the pigment in the medium and preserve its qualities for time immemorial.
The pictorial surface is also important but this will be for another article.
Chose Quality Paints and Brushes.
As a side note – chose artist grades paints. I personally recommend Old Holland or Michael Harding.
Student grade is merely dyed fillers and only imitate pigment which has a much greater lustre and richness and will remain so over time.
Stick to a limited palette and buy the best you can afford.
Buy artist grade brushes from Rosemary and co.
Jacksons stock Windsor and Newton and many other brands.
Synthetic brushes are very good these days if budget is tight.
If you like bristle brushes, Chung-king are the best.
Cheap brushes will easily lose their shape, don't hold paint well and quickly lose their bristles. Fishing stray hairs from your painting is no fun at all.
Medium For Alla Prima Painting.
For Alla Prima (painting in one sitting or painting en plein air) my preferred medium is a 50/50 mix of Poppy Seed oil and turps (linseed is also fine but Poppy Seed has less of a yellowing effect over time and sets up slightly quicker)
I will cover pictorial surfaces or painting grounds in another article.