In painting with oil, it’s standard to use white to lighten mixtures. White (whether lead white, titanium white, or zinc white) is incredibly useful as there are many colors that can’t be obtained without it. Contrariwise, there are also colors that can’t be mixed if you use white. White lightens, but it also cools (in most circumstances), decreases chroma (except when applied in small amounts with some cool colors), and increases opacity. There are some circumstances in which you want to lighten (increase the color’s value) without the other effects of adding white. For example:

• In traditional oil painting technique, it is often appropriate to keep shadows transparent. That basically means mixing shadow colors without any white.
• Because white usually decreases chroma, mixtures involving white can be lower in chroma than you want. As a result, painters sometimes complain of paint mixtures that are too “chalky.” They get lights that have a pastel look with low chroma. While that is sometimes exactly the right color (in which case no one complains) we sometimes want lights that are as high in chroma as possible.

While oil painters don’t generally depend on white-freen paint mixtures to nearly the degree that watercolor painters do, it’s important to know how to paint without white when you need to. If you just need a dark color, that’s easy. If you need to paint a range of values, then you’ll need to find mixtures that achieve that value range. The ease of doing so depends on what part of the color wheel you’re working with.

There are plenty of high-value yellows, for example. If you need to lighten a yellow or brown mixture, you can usually do so by mixing in a lighter yellow (I like lead-tin yellow for this purpose, or a cadmium yellow if I’m looking for higher chroma). Reds are more difficult—it’s hard to mix a light red without dropping the chroma (i.e., making it pink). Genuine vermillion is sometimes useful because it is somewhat light and doesn’t drop chroma in mixtures the way cadmiums of similar color can do. Oranges can be lightened by adding a lighter yellow and then, if necessary, adjusting back to the right hue with a bit of red. A yellow green can similarly be lightened with yellow.

Cooler colors (blue, green, blue-green, purple) are more difficult to lighten, since the tube colors in this range are often pretty dark. Some cobalt blues can be relatively light and therefore quite valuable (although they are also opaque, so they don’t help as much if you are looking for transparency).

The other solution, of course, is to paint thinly onto a white surface, just as in traditional watercolor. The method used by Ted Seth Jacobs and his students such as Tony Ryder, for example, typically begins with a “color wash.” That means applying the first layer of paint very thinly, mixed with dilutant. While wet, the color can be lightened by wiping away paint with a dry rag or brush; or one dipped in dilutant. In this method, the initial color wash layer is later painted over with opaque paint mixed with white. A similar method can be used with traditional glazing technique or when a certainly watercolor-ish look is desired.

If you’re not used to painting without white, a good exercise is to try to complete a painting while using white only when absolutely necessary. That can generate an overall range of value and chroma that is markedly different than a painting in which white is used liberally. If you struggle with “chalky” mixtures, a minimal white approach can really help.

• The easiest way to stretch a large canvas evenly seems to be to put it on the stretcher unprimed, somewhat loosely. How loose? Put the canvas on the floor flat under the stretcher. Tack the edges of the canvas to the back of the stretcher without pulling. You then size it with a thin layer of hide glue. The glue tightens the canvas. If you do it right, the canvas is taut with no wrinkles. This is easier than trying to get it right using canvas pliers and trying to make the tension even across the whole canvas.
• I like using regular office thumb tacks initially, followed by staples or copper tacks when you know you’ve got the tension exactly right.
• The lead oil primer made by Natural Pigments is very easy to apply. It is much less viscous than other oil primers I’ve tried. That means you don’t have to thin it and it’s less likely to get all over the place. It dries to the touch very fast. A potential downside is that it doesn’t tend to fill the weave of the canvas like thicker primers do.
• It’s good practice to rub the surface of the canvas lightly with a pumice stone before sizing in order to open the fibers up somewhat to accept the glue. If you do this, however, you will create small blobs of fabric in places. After priming, you’ll need to wet sand or use a knife to cut these away.
• Upper Canada Stretchers makes really good stretchers. Check out the discounts for good deals.

Because the structure of an oil painting is inherently complex, it’s always best to attempt keep both it and its various components as simple as possible. However, this element of simplicity should not necessarily extend to purchasing ready-made materials if the hope or expectation is to create higher quality work: generic materials have a strong tendency to produce generic work. While boutique materials are usually higher quality, this is not necessarily the case with the oil. And they still don’t impart the vital information about the nuts and bolts of the craft: at the end of the day, there is no real process, just a set of purchases, a pseudo-craft.

Go read the whole thing.

Badger brush set

Badger hair is traditional for making brushes used for blending oil paint, so I broke down and bought this set from Natural Pigments. There is a fan, a round, and two sizes of flats. So far, I’ve just tried the round, but for blending it is just lovely. I had been doing most blending with a synthetic round, and wow! The badger beats that by a mile. Highly recommended if you paint in a style that involves rendering. I wish I’d bought these a long time ago.

#2 Bristle flat brushes

These were cheap, so I bought a few. The handles are nicely laquered in a natural wood color. The ferules are firmly set and double crimped. The brush hairs are well set (flags facing inward), with the annoyance of a few stray hairs that needed trimming. The brushes hold their shape under heavy use and have the right level of resistance when moving paint. These are an excellent value for inexpensive brushes.

Velazquez medium

This is calcite ground with a blend of bodied and refined linseed oils. I’ve made basically the same stuff myself, but it’s convenient to have some already made up in a jar. It’s light gray and the consistency of oil paint. Mixed with paint it adds no color, but makes it more transparent. This is a good medium for velaturas and for making strongly tinting pigments less strong without losing body. I haven’t noticed that it has much effect on the brushing properties of the paint. They have a similar medium that’s specifically for impasto, but that’s not how I paint. This stuff won’t magically let you paint like Velazquez, but it is useful and inexpensive.

Recommendations include:

• Drawing a line along the weave of the canvas in pencil along the boundary beforehand, so that you can check to see that the edge of the stretcher is even with the canvas weave as you apply it to the stretcher chassis.
• Stapling or tacking from the edges of the canvas inward. This is exactly opposite from the way every other source I’ve seen says to do it.
• Using pushpins for the initial attachment of the canvas to the stretcher, for ease of adjustment, before final tacking or stapling.
• Letting the canvas settle onto the frame for a day or two, with adjustment as needed, prior to final tacking or stapling.

These methods differ from standard practice, but the author makes a good case.

(Note that I found this article via a related post by Randall Stoltzfus.

The whitest white I’ve been able to find is “radiant white” by Gamblin. It’s titanium white in poppy oil. Most of the time I prefer paints ground in linseed or walnut, but for this purpose it makes sense to use the whitest possible pigment and the most colorless binder available. I’m still painting out test strips on a neutral gray background, but I’d guess it’s a quarter Munsell value step than the next brightest titanium white I’ve played with. I’ll use it only when I need a very light highlight.

The darkest black I have is Williamsburg intense black. The pigment is listed as “carbon from gas flame.” The back label says: “warning: very slow drying.” It is just noticeably darker than bone (“ivory”) black. The slow drying can be compensated for somewhat with a drier such as lead napthenate. I will use it only for dark accents at the very last stage of painting, so drying time for this particular paint is not that important for me.

Update

2 May 2009:_ There’s a small highlight that I had previously painted in Old Holland titanium white. It’s light reflected from the shiny metal part of a clothes hangar. In real life this highlight is very noticeable, but on the painting, surrounded by relatively light tones, it did not stand out at all. I recently painted it in using pure Gamblin radiant white. It is noticeably brighter than before—giving an effect that is much more like what I was trying to depict.

This has been illustrated for me this week. The background of the painting I’m working on is a gradation of mostly lead white to lead white with a fair bit of raw umber. Raw umber dries quickly and promotes drying when it is a component of any mixture. Over the course of several days, I’ve observed the painting dry progressively from one edge to the other—the more raw umber, the faster the drying. The lead white part of the painting has not dried quickly at all.

Modern lead whites are made with a pigment called “basic lead carbonate.” Historically, lead whites were less pure. They contained basic lead carbonate, as well as other lead compounds that do dry fairly quickly. So older lead whites, such as those made using the traditional stack process, would likely act as driers. It may be that if you bought some stack process lead white from Natural Pigments and mulled it with oil, you’d have a fast drying white.

Other than that, you can make lead white dry more quickly by adding a small amount of lead napthenate or other drier, just as with any other oil paint. Or you can mix in some umber.

Dear David,

My question is in reference to “Paint Strings”. I’ve never heard this term before. Is this an oil painting technique? (I’m just learning to paint and I’m using slow drying acrylics if that makes a difference.) Can you one day do a blog posting about making paint strings.

Thanks, Michael. “Paint string” is an oil painting term because other kinds of paint dry too fast for it to be practical. What it means is to pre-mix a series of colors in a gradation from one color to another. Usually, the string goes from high value to low value at a single hue. Typically, chroma is highest in the middle of the range, because that mimics the progression of chroma across objects in the real world, and because that’s easiest to mix.

You can use paint strings in a couple of different ways. At one extreme is to just mix one or two strings that you think you’re likely to use. For example, you could have a string of neutral grays that you use to decrease chroma in mixtures (the best way to decrease chroma with minimal effect on other aspects of chroma is to mix in a neutral gray of the same value). You could also mix a string of “average” flesh color in preparation for working on a figure. Personally, this is usually how I work with paint strings.

At another extreme is a “set palette.” This means that you carefully plan out the colors you will be using and mix them all out before you begin painting. That way, you don’t worry about mixing as you work because the colors are right in front of you. Frank Reilly, for example, was a 20th century artist who taught a set palette method. Artists who work with set palettes often tube a bunch of their most commonly used mixtures so that they don’t have to spend so much time at the beginning of each painting session.

You can pre-mix color with water media, but you need to do something to preserve them over the course of your painting session. I have not tried the new slow-dry acrylic paints and have no real sense of how they behave. With oil paint, it just works that way naturally.

Here’s where the “White Shirt” painting is at. What I’ve done is finish initial rendering of each area of the shirt. I found that the hues were uneven—I am still learning to manage near-neutrals across relatively large areas of a painting. What I tried was to glaze transparent yellow oxide across bluer shadow areas, which evened out hues somewhat, but the overall painting was unconvincingly yellow-orange. I had also over-rendered much of the shirt, with too broad a range in value between darks and lights.

This was a perfect time to apply a velatura.

Taking a hint from Tad Spurgeon, I mixed up a batch of putty. This was calcite (ground marble dust) mulled with walnut oil and a bit of stand oil. The resulting mixture was a dull grey with the consistency of, well, oil paint. Putty is a medium used to increase the transparency of paint, since the calcite is essentially invisible in an oil vehicle. This is better than adding a lot of oil or resin, as the calcite/oil mixture is as strong and as resistant to discoloration as oil paint.

I mixed the putty with lead white (Doak’s flake 1C) in approximately equal amounts. Then I added a very small amount of neutral gray paint (ivory black and burnt umber) which I had previously tubed. I now had a very light gray, relatively translucent mixture.

I oiled out the surface of the painting with a thin layer of walnut oil, which is very slippery and less yellowing than linseed. I applied the gray mixture to the surface. Initially, it looked awful—my careful painting was covered with flat gray. With a stiff bristle flat, I started working at adjusting the thickness of the velatura layer, pulling the underpainting out. I found that it was effective to moisten the brush with a bit of walnut oil. It took awhile, but eventually the underpainting began to show through, with the value range compressed toward the gray value of the velatura and the hue pulled toward neutral.

It needs a bit of work once the velatura layer has dried to restate a few highlights and dark accents, but overall this was a successful exercise.

I love the M. Graham watercolors, so I am going to start there, but, I wonder: Can I use linseed oil with them as a brush cleaner without degrading the quality of the walnut oil? (Linseed is SO much more cost effective.)

Thanks, Alex. I’m not aware of any technical reason not to mix linseed with M. Graham oil paints (which are ground in walnut oil). M. Graham would much prefer that you buy oil from them, but inexpensive linseed will work just as well and is exactly as natural and nontoxic (don’t buy boiled oil or other hardware store linseed oil).

In fact, two of my favorite paint makers—Robert Doak & Associates and Blue Ridge Artist Materials—grind their paints in a linseed/walnut blend. You might want to check them out. M. Graham is of mid-range quality while theirs is high-end, but not all that much more expensive. All three brands are extremely smooth and brushable. You could mix paint from all of these brands together without any problems.