Glazing Skin Tones in Oil Painting
Following the classical Flemish method of oil painting, I have thus so far painted the Imprimatura, the Verdaccio, gone over the figure with Terra Verte, and completed the first semi-opaque flesh tone layer.
You can follow these previous steps on my blog or on Youtube if you’ve missed them.
Now comes the first glazing layer. Oooohhh… Ahhhhh..
But what is glazing?
For those noobs at oil painting, glazing is a term you’ll hear pretty early on.
Glazing is an indirect painting method (where the painting is build up in layers) and is the application of thin, slightly oily, transparent films of paint over a dry, opaque underpainting. Because the paint layer is very thin and transparent, light refracts off the layers beneath it, and creates a beautiful glow of glossy colour that is impossible to achieve simply by direct painting methods.
Here’s a bit more information about scumbling and glazing that I wrote about in a previous blog, Painting the Traditional Way – Final Glazing
Using just a little medium
Usually a little medium in the form of linseed oil, or an alkyd resin is added to the paint on the palette used for glazing. This aids the spreadability and flexiblity of the paint film and keeps us safely adhering to the fat over lean rule.
But remember to use as little medium as possible to avoid some nasty paint film effects like yellowing, wrinkling, or too much gloss so that the subsequent layer won’t stick to it, or drying issues, where the paint film will struggle to dry due to excessive oil.
Some artists simply use very good quality brands of paint straight from the tubes without applying any solvents or oil mediums, because the way the paint comes from the manufacturer, is generally the best balance of oil binder to pigment.
They achieve their glazes and scumbles by brushing in very thin layers of paint on top of a well-dried underpainting.
I put well-dried in bold because you want to make sure that the underpainting layers are durable and dry before adding the glazing layers on top, and which usually contain more oil and will thus prevent the layers beneath them from properly drying by oxidation. (Oil paint films dry by oxidation by the way.)
Because I hadn’t been able to work on this painting for a few months, I at least had the advantage of having a really dry painting before beginning the glazing stage.
Making a medium for glazing
I’ll talk more about oil painting mediums another time, because that is quite a large topic.
It’s good to experiment with different mediums and learn what works best for you, but I am keeping things pretty simple here.
I made a very basic medium of 2 parts of refined linseed oil, 1 part solvent (odourless mineral spirits) and 1 part alkyd resin.
Just a few drops of medium are all that’s needed to aid in the flow and flexibility of the paint.
I prefer to work very thinly and build up successive durable paint films which are less resistant to defects, and allow enough drying between the layers, than to apply one thick coat of paint which takes longer to dry and is more susceptible to cracking.
Beading on the surface? Insolence! Pesty painting!!
If I find the paint ‘beading’ on the surface of the canvas, it means that there’s too much oiliness in my mixture and the canvas surface is too slick and slippery. I then just dab the area with a rag and apply slightly more pigment to oil ratio on my palette and softly brush the paint on the canvas. The physical action of ‘brushing the paint in’ seems to break the surface tension of the previous layer.
You can also add some Venice Turpentine or Canada Balsam (which are both natural resins) to your mix if the beading is really annoying you.
I stick to using just a medium of linseed oil and solvent in the underpainting layers and avoid liquin or alkyds until I get to the glazing layers. This seems to mitigate beading problems because alkyd resin can make your canvas surface quite slippery.
Using a couch
As in, not for psychological therapy, but when you take a rag and rub in a tiny amount of medium onto the surface of the dried canvas in the area where you intend to work. This helps to lubricate the surface and aids in better adhesion for the fresh paint on top of the dried underpainting.
It’s also a good technique to prevent using too much medium, because you can apply your paint straight from the tube and work it in very thinly and gently.
The colours I used for glazing the skin
To build up the warmth of the flesh over the rather ghoul-like appearance of the underpainting layers, I needed to use warm colours.
Therefore I stuck with using the following artist quality Winsor & Newton colours: permanent rose, light red, and gold ochre. These are all transparent colours with a fairly strong tinting strength. So only a thin application is necessary.
These pigments were mostly used for the first semi-opaque flesh tone layer that I applied over the verdaccio before, so my colour palette is balanced and simple.
For now, I’m allowing the cool tones of the verdaccio to shine through the warm fleshy layers and thereby balance the warm and cool colours to create more realistic looking skin.
I’m building this painting up slowly with many thin oil glazes, so I may add a cool colour glaze near the final stages.
Try to use no more than two or three pigments in your glaze at a time. This makes your colour mixing easier to handle, allowing you to adjust the chroma and tinting strength, and also prevents muddying up of your colour.
Beautiful effects can be created by keeping your paint film transparent and subtle. You don’t need a lot of paint. Or medium.
Once I was done with the skin, I decided to go ahead and glaze the hair with pure burnt umber. And then continue with the dress and the white background.
The importance of painting the background
It’s always a good idea, when painting portraits especially, to paint the background or the surroundings at the same time as the subject.
This is because colours and values appear differently when juxtaposed to other colours and values. We all know those funny eye tests where you’re asked to choose the darker or lighter colour between subject A and subject B, but then the answer is that the colour is exactly the same.
So bearing this in mind, I glazed pure ultramarine blue over the dress and whitened up the background.
The immediate effect was that suddenly the flesh didn’t look so cold anymore.
The temperature of this painting is particularly cool, with the blue of the dress and the cold lightness of the room.
The ultramarine blue of her dress reminds me of the lapis lazuli robe of the Madonna as seen in countless Renaissance paintings and frescos.
So I want to make it an intense and deep blue through many thin glazes.
Be careful with large areas of white
I’ve noticed before that large areas of thickly painted white are quite susceptible to cracking within as little as 10 years.
I think and I’ve read that zinc white is usually the culprit. Or a badly primed canvas. But anyway, I tend to be a bit more careful with large areas of white now.
Therefore I made sure that the paint on my palette was well mixed with the medium, and I applied the white paint to the background in a very thin, but slightly oily layer.
I’d rather paint 2 or 3 thin, transparent layers of paint, than one thick opaque layer, which may not be so flexible and may start cracking.
Besides, I like the way the warm underpainting tones of the background are showing subtly through the semi-opaque white.
Next, I’m going to allow this painting to dry for a few days. Then I’ll continue with more glazing and adding details, highlights and shadows.