Penny-wise, pound foolish

Cheap materials or weird deviations from process inevitably lead to disastrous results, but artists keep doing it.

Untitled (Floral), 1960, Morris Louis, showing deterioration of untreated cotton duck ground, courtesy the Museum of Fine Arts, Houston (it’s since been restored).

This week, I’m assembling materials for my watercolor workshops aboard schooner American Eagle. I’m giving them QOR watercolors by Golden. These are professional-quality paints, not student-grade—even though some of my students will have never painted before. I want to create impassioned painters, and bad materials are the best way to nip creativity in the bud.

Cheap materials are only part of the problem. There’s a mistaken association between ephemeral materials and ‘authenticity’ that arose in the latter part of the 20th century. It echoes today, and drives artists to experiment with painting on cardboard, collaging paper with oil paints and other unstable methods.

Misty Moonlight, c. 1885, Albert Pinkham Ryder, courtesy Crystal Bridges Museum of American Art

“I was beginning to wonder if it was just the art historian in me, but I see people using such unbelievable crap in their artwork and it makes me shake my head,” a reader wrote.

There are vogues that sometimes result in spurious results. Oiling out is a traditional technique where a hint of linseed oil is applied to a dried layer to make the next layer appear to sink into it. A variation appeared about a decade ago. Painters would paint into a soup of wet medium. It was supposedly okay because the medium was fast-drying alkyd, and it allowed mediocre painters to produce something that looked like Tonalism.

Moonlight, c. late 1880s–1890s, Ralph Albert Blakelock, courtesy Phillips Collection

I was immediately reminded of the sad fate of Ralph Blakelock’s paintings. He was a Tonalist, also interested in luminosity. He tinkered with his paint application in search of new effects. Unfortunately, many of his canvases are badly deteriorated because of it.

Another painter whose work has rotted out because of bad technique is Albert Pinkham Ryder. Ryder built up his paintings with layers of paint, resin, and varnish applied haphazardly on top of each other. He painted into wet varnish and disregarded the different dry times of his pigments. He experimented with candle wax, bitumen and novel oils. That gave his paintings the luminosity that he was aiming for, but at a price.

Paintings by Ryder are consistent only in their instability. They’ve darkened seriously over time and developed terrible cracks and crazing. In some cases, they’ve never fully dried or have completely disintegrated.

There are only a few oils with natural drying properties. These are linseed, tung, poppy seed and walnut oil. Non-drying oils like almond or olive oil are never suitable for oil painting

Similarly dubious is the process of starting a painting in acrylics and then finishing it with oils. It’s unnecessary once the painter masters the process of wet-on-wet painting, and it has no long history proving it to be archivally sound. We know that the reverse (acrylic over oil) delaminates almost immediately. That means the layers do not bond.

I learned to paint back in the 1970s with a homemade medium comprised of turpentine, Damar varnish, linseed oil and a drop of cobalt drier. It was fairly standard for the time. I used it until I spent a day wandering around the Albright-Knox Art Gallery looking at the terrible cracks and crazes in Clyfford Stillpaintings. The 20th century masters are not paradigms of painting technique; many of their paintings are now in terrible shape. Zinc oxide grounds were much in vogue at the time, and the heavier cadmium pigments are pulling away from them now.

Companies like Grumbacherand Gamblin hire chemists to make and test materials. I trust them far more than I trust my own judgment in chemistry.

Bad grounds are a chronic problem for conservators. “Morris Louis did wonderful color work on unprimed canvas,” my reader noted. “Museums tear their hair out.” Yes, a good ground can be expensive, but it will extend the life of your paintings—and make the painting itself easier. If you insist on painting on cardboard, make sure you insulate it from your paint with an acrylic or PVA sealant.

Oil painting is 1400 years old. There’s not much that hasn’t been tried in that time, and the standard protocol we use today is the result of that trial-and-error. Cheap materials and weird deviations inevitably lead to disastrous results, but artists keep doing it. That’s a misdirection of creativity.

A little knowledge is a dangerous thing

Chemistry was my worst subject, so it’s ironic that it plays such an important role in painting.

Blueberry barrens, watercolor on Yupo, Carol L. Douglas, available through Maine Farmland Trust Gallery.

My students ask me, on average, a question a week that I can’t answer. Often, these revolve around chemistry. This was my worst subject, so it’s ironic that it plays such an important role in painting. Because I care about the survival of paintings, I really wish I’d paid more attention in high school. Let that be a lesson to you, kids.

I like painting with saltwater in my watercolors. It’s a habit I picked up from Poppy Balser, who also lives along the North Atlantic. It encourages the separation and granulation of the colors, adding just a bit of texture to the whole process. In addition, I occasionally—like many other watercolorists—add salt to create more texture.

Float, watercolor on Yupo, Carol L. Douglas, available.

“But won’t salt degrade the paper?” a student asked. In searching the internet, I found dissenting opinions. The ones that said it would, thought it would do so by lowering the pH of the paper. Acidity is the enemy of paper, a fact known even to dolts like me.

Now, the idea that salt was acid-forming didn’t make much sense to me. Table salt is neutral; you can tell by its taste. I asked my husband, who had the same chemistry teacher as me, but was good at it. He mumbled something about salts being chemical compounds consisting of cations and anions. Suddenly, I remembered just what it was I disliked about the subject.

Bunker Hill Overlook, watercolor on Yupo, Carol L. Douglas, available .

Well, it would be easy enough to test, I thought. I just needed to find some pH test strips. That was complicated a bit by the fact that we live a little to the north of nowhere, and everyone sensible has left for the winter. Eventually, I ordered some online.

At the post office, I tucked them in my jacket pocket. They were promptly filched by my dog. I can now tell you that my dog’s saliva has a pH of 8.5. This is, interestingly, considerably more alkaline than human saliva, which I looked up. Our mouth drippings have a pH normal range of 6.2-7.6.

What was left of my test strips after Guillo ate them.

There were enough strips left to test the raw paper (Strathmore), an area where I’d painted without salt, and a section where I’d used enough salt to create a new ocean. Both painted samples were slightly more acidic than the unpainted paper itself, which was neutral.

Any real scientist would be appalled by my technique. I wet the paper with the spray bottle in my watercolor kit. That contains common tap water, but I figured that whatever impurities it contained would affect all the samples equally. I then stuck the samples down with my index finger—more or less clean—and waited. But I think the results were good enough to tell me that salt doesn’t really affect the pH of the paper. But paint itself does.

My conclusion: salt doesn’t make any difference, but paint itself does.

All of which reminded me of a hoary old joke you hear from kids, about dihydrogen monoxide, which is a colorless, odorless, tasteless liquid that’s in everything we eat or drink. I was thinking about it when I rinsed my hair with the stuff this morning, after scrubbing it with a chemical bath that was a surfactant combined with a co-surfactant, and then rinsing with a polymer. Why do we find the results of that so pleasant, and our dirty hair so offensive?

But, more importantly, I was thinking of a little ditty that’s been with us since the early 18th century:

A little learning is a dangerous thing;
drink deep, or taste not the Pierian spring…
(Alexander Pope)

It’s why I discourage people from making their own mediums, experimenting with substrates, etc. Painting is hard enough when we’re using proven technique. It’s hard enough for conservators to preserve paintings that were done properly. Why make things more difficult?

Georgia O’Keeffe has an acne problem—and she’s not the only one

Artists are, for the most part, practical chemists with no education in the subject.
Pedernal, 1941, Georgia O’Keeffe, courtesy Georgia O’Keeffe Museum. All three paintings in this post have been identified as suffering from saponification.
For decades, conservationists, scholars and even Georgia O’Keeffeherself assumed that the tiny bumps along her paintings were grains of sand from the desert of New Mexico. Eventually, those bumps began to grow and flake off.
The bumps are metal soaps, formed by a chemical reaction between lead and zinc pigments and the fatty acids in the linseed oil binder. Medieval alchemists made boiled linseed oil by exploiting this same reaction, tossing lead oxide in to make the oil thicken.
O’Keeffe’s paintings aren’t the only ones suffering from these surface pimples. The problem is found in works by artists as diverse as Rembrandt and Vincent Van Gogh. As many as seven in ten museum masterpieces may be affected.
The Anatomy Lesson of Dr Nicolaes Tulp, 1632, Rembrandt courtesy the Mauritshuis 
Anecdotal evidence shows that moving paintings, exposing them to daylight, and changes in humidity contribute to the problem. “There seems to be some correlation between the number of times the paintings have traveled to public exhibitions and the size and maturity of the surface disruption. The more times the paintings have traveled, the more likely it will be that the protrusions are larger and more numerous, saidDale Kronkright, head of conservation at the Georgia O’Keeffe Museum.
Detail of Madame X (Madame Pierre Gautreau), John Singer Sargent, 1884, showing saponation in the black dress.
To test this theory, a team from Northwestern’s McCormick School of Engineering has developed a handheld scanner to document continuing changes in painting.
“If we can easily measure, characterize and document these soap protrusions over and over again with little cost to the museum, then we can watch them as they develop,” saidOliver Cossairt, an associate professor of computer science at McCormick. “That could help conservators diagnose the health and prescribe treatment possibilities for damaged works of art.”
What does this have to do with us working artists? After all, we’re not using lead paint anymore, and if we’re smart, we don’t use zinc white, either. The problem is, most artists are all practicing chemistry with very little education in the subject, self included.
Falling Leaves, 1888, Vincent Van Gogh, courtesy Van Gogh Museum
Don’t think you’re getting away from the metals because you’ve moved to a modern palette. Metals are naturally-occurring elements of great usefulness, and that includes making pigments. An incomplete list of the metal pigments we currently use includes cobalt blue and violet, manganese blue and green, ultramarine blue, the cadmiums, Prussian blue, viridian, the iron oxide pigments (sienna, umber, and black), and titanium white. In other words, you can’t get away from them. Nor can you get away from the fatty acids in oil binders. Whatever the binder you’re using—walnut oil, beeswax or linseed oil—it’s an organic fatty acid.
This process of saponification is also what is going to make you and I dissolve into a pile of grave wax someday. Even the ancients knew that nothing lasts forever: “Then I considered all that my hands had done and the toil I had expended in doing it, and behold, all was vanity and a striving after wind, and there was nothing to be gained under the sun,” (Eccl 2:11)
Meanwhile, we’ve managed to keep paintings intact for a few thousand yearsand we can continue to do just that. Just continue to paint fat over lean, avoid known fugitive or reactive pigments, and don’t follow untried, crackpot approaches, and your work should last a long time.

If it was good enough for my grandfather

Was litharge in earlier paintings, or did Rembrandt just get lucky?
Rembrandt’s impasto.
I’m constantly railing about using time-tested technique in your painting. Painters have been experimenting with weird additives in their paints for centuries. The results are often disastrous. Rembrandt van Rijn may be the exception that proves the rule.
Now, 350 years later, we tend to think of Rembrandt as the model of traditional art. That’s especially true since, through most of the 20thcentury, his indirect painting techniques were taught as a sort of ‘purer’ painting in reaction to the volatility of Abstract-Expressionism.
It’s easy to forget that he and his Dutch Golden Agefellows were highly innovative, creating whole new genres of painting and challenging the Baroquestatus quo.
Portrait of Marten Soolmans, 1634, is one of three Rembrandt paintings in which plumbonacrite has been found. Courtesy of the Louvre.
Rembrandt’s is probably the most-studied technique in art history. We know his palette: lead white, ochre, Cassel earth, bone and ivory char, vermillion, madder lake, yellow lake, lead-tin-yellow and very limited use of azurite and ultramarine blue.
We know that, in his later paintings, he used moody glazes of dark color punctuated by fat impasto passages of pure light, often modeled with a soft brush after they were laid down. These impasto layers were then glazed with color.
Susanna and the Elders, 1647, is one of three Rembrandt paintings in which plumbonacrite has been found. Courtesy of the Staatliche Museen zu Berlin.
For that he needed a thick, fast-drying white. The danger with that is brittlenesss and cracking. Adding lead and heat-treated oils kept the paint layers more pliable over time. So Rembrandt used a combination of lead white, chalk, and smalt (ground glass). His paintings look great today.
Recently, researchers have found traces of a lead carbonate mineral— plumbonacrite—in three of Rembrandt’s best-known paintings. They’re terrifically excited, because the previously earliest-known appearance of plumbonacrite was in Vincent Van Gogh’s Wheat Stack under a Cloudy Sky (1889).
Wheat Stacks under a Cloudy Sky, 1889, Vincent Van Gogh, Kröller-Müller Museum
Since lead is cheap and plentiful, it’s been used in paints since antiquity. But it can darken or fade other pigments. In 2015, chemists were trying to figure out what was damaging the red lead pigment in Van Gogh’s picture. In the space between the sample’s reddish-orange Pb3O4 core and the light blue PbCO3 layer that surrounds it, they found plumbonacrite. That was the first time it was ever seen in a pre-20th-century painting.
How did Rembrandt manage to get plumbonacrite into his paintings two centuries before it came into common use? “[O]ur research shows that its presence is not accidental or due to contamination, but that it is the result of an intended synthesis,” wroteVictor Gonzalez of the Rijksmuseum and Delft University of Technology.
Bathsheba at her Bath, 1654, is one of three Rembrandt paintings in which plumbonacrite has been found. Courtesy of the Louvre.
Their best guess is that it came from litharge, which is an oxide of lead used to refine silver. In the seventeenth century litharge was made by pumping a set of bellows to send very hot air across molten lead, creating the oxide and sending it flying into a nearby receptacle. If this sounds dangerous, it is.
Litharge did create some pretty colors. Litharge of gold is litharge mixed with red lead, which may have been how Van Gogh acquired it. Litharge of bismuth is a brownish silver color—just the kind of color that would appeal to Rembrandt, in fact.
Why would Rembrant have even considered adding litharge to his paint? The most obvious possibility is that it was in use all along, and appears in other, earlier paintings that scientists haven’t examined yet. Or, Rembrandt was messing around and got lucky.

Falling apart

A plea to use traditional materials and practices in painting, whenever you can.
American Landscape with Indian Camp, by Ralph Blakelock, showing the damage that can result from tinkering with technique.

Yesterday I mentioned the deterioration in Albert Pinkham Ryder’s paintings. He was not, by any means, the only painter whose work has suffered over time.
Prior to the 19th century, painters had a limited range of materials at their disposal: vegetable oils, waxes, plant gums and resins, and eggs, milk, and animal hides. Pigments were made by either grinding minerals or extracting dyes from plants and insects.  Some of the extracted pigments turned out to be fugitive (meaning they aren’t light-fast) but generally those old paintings are in remarkably good condition.
Holy Virgin Mary by Chris Ofili. Now, seriously, how does a conservator preserve elephant dung stuck to a canvas?
The 19th and 20th centuries were a period of constant modification of materials. Some changes have been inarguably for the better—for example, there would have been no Impressionism had there not been an explosion of new pigments in the mid-19th century.
Whenever I visit the modern collection at the Albright-Knox Art Gallery I am struck anew by how badly some of their paintings have aged.  20th century artists had no reason not to use the tremendous variety of synthetic materials that industry was creating—synthetic media, plastics, adhesives, and drying agents. As the definition of what constituted painting broke down, artists also incorporated materials the ancients would have understood to be ephemeral or beneath their calling: dung, straw, paper, urine, blood, etc.
Woman, by Willem de Kooning, 1965. He definitely experimented with obscure additives to keep his paints open longer, but so far scientists haven’t actually found any mayonnaise in his paintings.
Willem de Kooning, for example, allegedly mixed house paint, safflower oil, water, oil and egg in with his paints. Some surfaces of his paintings remain soft and sticky fifty years later, which has to present a bit of a problem for conservators. Anselm Kiefer has used lead, sand and straw in many of his paintings.
Learning to paint in the 1960s and 1970s, I used a medium made of equal parts varnish, turpentine and linseed oil, with a few drops of cobalt drier thrown in. Having seen the ghastly cracking of fifty-year-old paintings made with this medium, I decided that medium shouldn’t be a DIY project. Better to trust the scientists who work for the reputable paint manufacturers.
Mildew attacking orange paint in a Clyfford Still painting. Courtesy Clyfford Still Museum.
Another technique I discontinued is underpainting my oil paintings in acrylics. Certainly, oil-over-acrylic won’t delaminate the way acrylic-over-oil will, but who can say how the two paint systems will interact over time? I think it’s fine to paint in oils on acrylic-primed canvas, but any part of the painting that shows through (and that includes the toning) should be done in oils.
It was trendy a few decades ago to dismiss the archival aspects of painting, to embrace the ephemeral. If de Kooning is the equal of Rembrandt, why would we not want to see his works survive for the ages?
This post first appeared on October 6, 2013. I realize my use of Yupo is inconsistent with this viewpoint, but I believe it to be chemically compatible with watercolor. 

In looking for this, I came across posts about the 2013 government shutdown. The more things change…

Water-miscible oils

They’re marketed as easier and safer than traditional oils. Are they?
Fitz Hugh Lane Day at Camden, by Carol L. Douglas. This would have been impossible to paint with water-miscible oils. They run at the first hint of atmospheric moisture.
Yesterday I got a note from a fellow professional mentioning that she’s finally seen the last of her water-miscible oil (WMO) paints. I was surprised she’d lasted this long.
Water miscible oil paint is engineered to be thinned and cleaned with water, thereby avoiding the supposedly-harmful use of turpentine. But few painters use turpentine anymore. It has been overwhelmingly replaced by odorless mineral spirits. Still, WMO are perceived as somehow ‘safer’ than regular oil paint.
Of course, the toxicity of paint rests not in its binders, but in its pigments. The heavy, or toxic, metals like copper, cobalt, cadmium, and lead are the worst. It’s impossible to avoid them completely, but when you buy paints, consider not just your own safety, but that of the poor schmoe in China who has to make them.
Traditionally, pigments were made in a binder of drying oil—flax, walnut, safflower or egg yolk—or gum Arabic, in the case of watercolor. All of these binders are organic, by the way. In the 20th century, we saw new binders developed, including alkyds, vinyl and acrylics. Water-miscible oils are in this class of engineered polymers.
Squall on Lake Huron, by Carol L. Douglas. I got soaked; so did my painting.
Most brands add an emulsifier, or detergent, that allows the linseed oil to accept up to 25% water by volume. Since emulsified paint rapidly becomes stodge, it’s wise to use as little water as you can with these paints.
Holbein’s Aqua Duo manipulates the polymer to accept water in a loose bond at the end of the chain. These paints contain no detergent. They tend to be less gummy than other WMO. However, they are marketed to be mixed with acrylics. Acrylics and oils dry so differently that this promises to be an archival disaster.
When this happens, the oil painter ducks, but can save his painting. WMO are immediately ruined.
WMO are designed to handle like oil paints, but in practice, they don’t. When thinned to a wash using water, they may refuse to adhere to the ground. At middle thicknesses, they dry more like gouache than like oil, with a flat surface and color shift. As impasto, they have the consistency of oatmeal. Like acrylics, their transparency changes as they dry. The paints have a different flow rate than conventional oils, so you can’t really place a long, lovely line with a loaded brush.
              
All oil paints dry through oxidation, but first the water-soluble oil must disperse the water through evaporation. That leaves the final surface slightly tacky to the touch.
Oil painters have been known to pick off the water droplets right before a sale. That’s impossible with WMO.
Most paint looks pretty good the moment it’s applied to a canvas. The question is, what will it look like when it’s been drying for a few hundred years? Oil paints develop cross-linked polymers that create a strong, tough surface over time. How will the emulsifier in water-miscible oils affect that? I don’t know, and neither does anyone else. They haven’t been around long enough.
How do manufacturers suggest you work around the technical limitations of WMO? By adding oil-based media to their product line: stand oils, quick dry media, or alkyds.
All of which defeats the purpose. Here’s a news flash: traditional oil painters wash our brushes with soap and water, too. I use a saddle soap, but any super-fatted soap will do. That’s because soap—like detergent—is an emulsifier. Soap is made up of molecules with different ends. One end loves water. The other end loves oil. It’s the same principle as the detergent in water-miscible oils, but applied at the end, where it can’t harm your painting or technique. Just rinse the solids out of your brush in your slops tank first, and you’ll find that oil brushes wash easily.

Growing pain

The Yellow Christ, Paul Gauguin, 1889, is no longer the “art of the present” but it’s one of my favorites at the Albright-Knox. 
The Albright-Knox Art Gallery has announcedthat it plans an addition to its venerable space on Elmwood Avenue in the city of Buffalo. While it’s true that the current 19,000 square feet of floor space is crammed, one wonders—of course—who is going to pay for the addition.
The museum’s collection contains about 6,740 works, of which it can only exhibit about 200 at a time, according to Thomas R. Hyde, president of the museum’s board. “Campus development is no longer an option; it is a necessity,” he added. “We are, in many ways, a middleweight museum with a heavyweight collection.” And then he mentioned the cracks in the marble floors of the gallery’s original building.
(Veterans of capital campaigns will recognize that last gambit: throw in some deferred maintenance and people are supposed to stop kvetching about major changes.)
Side of Beef, Chaim Soutine, c. 1925, is another of my favorite Albright-Knox pieces.
Meanwhile, gallery director Janne Siren insists that plans are still in the ‘conversation’ phase. Having said that, the board has been rattling the can for expansion since publication of their 2001 strategic plan.  “Siren took over the directorship of the Buffalo gallery shortly after city fathers in Helsinki, Finland rejected a plan he had spearheaded to build a large Guggenheim museum there using public funding,” reported WGRZradio.
In 2007 the Albright-Knox Art Gallery deaccessioned a Roman bronze sculpture that subsequently netted $28.6 million at Sotheby’s. It was part of a larger deaccessioning of works that fell outside the ‘core mission’ of the gallery, which then-director Louis Grachos defined as “acquiring and exhibiting art of the present.” Alert Buffalonians immediately wondered what that meant for their own favorite works.
The deaccession vote was approved only on the contingency that the funds raised would be used to buy additional artwork. That meant that the money from the sale would be added to the paltry $22 million acquisitions endowment. (The overall endowment of the museum was then about $58 million.)
Being from Buffalo, I first visited the Albright-Knox while in diapers. Deaccessioning the Roman sculpture and clearing that exhibition space for other work was the right thing to do. But I share the Buffalo cynical mind, and I have my doubts about the viability of this project.
Buffalo is now half the size it was the year I was born, and there’s no sign that the population drain will abate any time soon. Clearly the board is counting on tourists to make up their numbers, and with the elegant expansion of the Burchfield-Penney Art Centeracross the street, an argument can be made that an arts corridor is possible on Elmwood Avenue.

La Maison de la Crau (The Old Mill), Vincent van Gogh, 1888, is another Albright-Knox piece that can no longer be termed ‘of the present.’ 

But that doesn’t address the question of how it will be paid for, or where the expansion will go. The Albright-Knox is landlocked, with Delaware Park at its front and Elmwood Avenue by its back door. Any kind of significant expansion would infringe on its parking lot, its neighbors, or the park.
1957-D No. 1, Clyfford Still, 1957. The Albright-Knox has a large collection of Still’s paintings. Last time I was there, I noticed how many 20th century paintings needed conservation. It’s not as sexy as expansion but still necessary. 
I await future developments with great interest.

Message me if you want information about next year’s classes and workshops.

Local artist

The Tiger, 1929, Charles Livingston Bull, for Barnum and Bailey.
I was trying to locate a show by a friend last week. Google came up with a number of references to her paired with the phrase “local artist.” It’s a funny term, and one I dislike.
There are local movements in art communities (such as the Northern California Tonalists or the Bay Area Figurative Movement) but in general most of us are working within the broader movement of our age. This is particularly true in today’s world, where boundaries are blurred by the internet.
Even worse is the term, “well-known local artist.” It’s amazing how many artists are unknown in their home towns and well-known elsewhere.
Saturday Evening Postcover art, March 6 1918, by Charles Livingston Bull
Consider the wildlife artist Charles Livingston Bull. Born in West Walworth, New York, he demonstrated an aptitude for drawing at a very young age. He enrolled at the Rochester Athenaeum and Mechanics Institute (now Rochester Institute of Technology) to study drafting, and took a taxidermy apprenticeship at the Ward Museum of Natural History.
Professor Ward sent the young man to the 1893 Chicago World Exposition to design a bird display for the government of Guatemala. His work there garnered him the job of Chief Taxidermist at the National Museum in Washington. Bull took night classes at the Corcoran Gallery of Art for seven years, until he felt ready to pursue a freelance animal illustration career.
Boys’ Life cover art, Apr 1932, by Charles Livingston Bull
He illustrated more than 135 books and numerous articles for magazines, including The Saturday Evening Post, Life, Collier’s, American Boy, and Country Gentleman. As exquisite as his drawings are, he’s pretty much an unknown here, in his hometown.

Let me know if you’re interested in painting with me in Maine in 2014 or Rochester at any time. Click here for more information on my Maine workshops!

Falling apart

American Landscape with Indian Camp, by Ralph Blakelock, showing the damage that can result from tinkering with technique.
Yesterday I mentioned the deterioration in Albert Pinkham Ryder’s paintings. He was not, by any means, the only painter whose work has suffered over time.
Prior to the 19th century, painters had a limited range of materials at their disposal: vegetable oils, waxes, plant gums and resins, and eggs, milk, and animal hides. Pigments were made by either grinding minerals or extracting dyes from plants and insects.  Some of the extracted pigments turned out to be fugitive (meaning they aren’t light-fast) but generally those old paintings are in remarkably good condition.
The 19th and 20th centuries were a period of constant modification of materials. Some changes have been inarguably for the better—for example, there would have been no Impressionism had there not been an explosion of new pigments in the mid-19th century.
Holy Virgin Mary by Chris Ofili. Now, seriously, how does a conservator preserve elephant dung stuck to a canvas? (And in this case, does it really even matter?)
Whenever I visit the modern collection at the Albright-Knox Art Gallery I am struck anew by how badly some of their paintings have aged.  20th century artists had no reason not to use the tremendous variety of synthetic materials that industry was creating—synthetic media, plastics, adhesives, and drying agents. As the definition of what constituted painting broke down, artists also incorporated materials the ancients would have understood to be ephemeral or beneath their calling: dung, straw, paper, urine, blood, etc.
Woman, by Willem de Kooning, 1965. He definitely experimented with obscure additives to keep his paints open longer, but so far scientists haven’t actually found any mayonnaise in his paintings.
Willem de Kooning, for example, allegedly mixed house paint, safflower oil, water, oil and egg in with his paints. Some surfaces of his paintings remain soft and sticky fifty years later, which has to present a bit of a problem for conservators. Anselm Kiefer has used lead, sand and straw in many of his paintings.
Mildew attacking orange paint in a Clyfford Still painting.
Learning to paint in the 1960s and 1970s, I used a medium made of equal parts varnish, turpentine and linseed oil, with a few drops of cobalt drier thrown in. Having seen the ghastly cracking of fifty-year-old paintings made with this medium, I decided that medium shouldn’t be a DIY project. Better to trust the scientists who work for the reputable paint manufacturers.
Another technique I discontinued is underpainting my oil paintings in acrylics. Certainly, oil-over-acrylic won’t delaminate the way acrylic-over-oil will, but who can say how the two paint systems will interact over time? I think it’s fine to paint in oils on acrylic-primed canvas, but any part of the painting that shows through (and that includes the toning) should be done in oils.
It was trendy a few decades ago to dismiss the archival aspects of painting, to embrace the ephemeral. If, say, de Kooning is the equal of Rembrandt, why would we not want to see his works survive for the ages?

One more workshop left this year, and it starts a week from today! Join me or let me know if you’re interested in painting with me in 2014. Click here for more information on my Maine workshops!