All Content Copyright © Michael Chesley Johnson AIS PSA MPAC

Sunday, February 5, 2023

New Blog Series on Color, Part 6: Blue

View in browser

Blues from Gamblin Artists Colors


Blue is a color that has more effect on the landscape than one might think.  Question:  How many light sources are there in the landscape on a sunny day?  The man-on-the-street would say just one, the sun.  But plein air painters know there is a second light source, the sky.  The light provided by the noontime sun (on average) tips the scale at 111,000 lux—lux being a measure of illumination—but the sky alone measures a whopping 20,000 lux.  This is nearly 20% of the sun's illumination.  (A full moon, which can seem quite bright, shines at only 0.25 lux.)  

And what does the light from this second source do?  A clear sky at noon has a light temperature of around 7000°K, which is a blue light.  The sun, on the other hand, has one of around 5000°K, which sits a little more toward yellow on the spectrum.  (An incandescent light bulb glows at a very yellowy 3600°K.)  So, on a clear day, the sky throws a considerable amount of blue light onto everything, not just the shadows but even the open, unobstructed landscape.  Most often, though, you won't see this as a definite blue cast but will sense it more as a general cooling-down of colors.

HISTORY

Blue has long been an essential hue.  Before the invention of synthetic pigments, it was the only color that could provide a cool contrast to warm earth colors.  The ancients had Egyptian Blue, a glass made from copper and sand.  Replacing this in the 16th century was Smalt, a finely-ground glass made with cobalt.  In Renaissance times, a method to refine a very pure blue from the precious mineral lapis lazuli was discovered.  Lapis, or Ultramarine Blue, was so highly prized that it cost more than gold—understandably, since it was hauled over the dangerous Silk Routes from a remote part of Khorasan (now Afghanistan) and passed through many hands before arriving in Europe.

The creation of modern blues was haphazard at first.  Prussian Blue was discovered serendipitously in 1724; Cobalt Blue, also by accident, in 1807.  Then, in the 1820s, the French government, wanting to find a cheaper alternative to the not-to-be-matched beauty of Lapis, offered a 6,000-franc prize to anyone who could make it for less than 300 francs per kilo. Finally, in 1826, a process was invented to make French Ultramarine, giving impoverished painters who weren't under the employ of a nobleman or the Church a cheap and plentiful supply of blue.  Since then, a variety of organic (carbon-based) pigments have been created, including Phthalo Blue in 1928.

USAGE

Although Ultramarine Blue is the most common blue used by painters, each painter seems to have a favorite "other" blue:  Cobalt Blue, Cerulean Blue, Sevres Blue, Indanthrone Blue—the list goes on.   Cobalt seems to be #2 on most palettes, right after Ultramarine, filling out the split-primary palette.  Ultramarine is a warm blue with a slightly purple cast; Cobalt, which has no purple, a cooler blue.

But to my somewhat deuteranomalic eyes, Cobalt Blue isn't visually different enough from Ultramarine, especially when in a tint.  So instead, I prefer a more greenish blue, Cerulean Blue Hue.  (I prefer this over the genuine pigment, which is more expensive and weakens too much when mixed with white.)  This gives me a wider temperature difference between the two.

I use Ultramarine Blue for a sky approaching the zenith, as the blue there seems darker and redder.  Lower down toward the horizon, where the blue is lighter and greener, I use Cerulean Blue Hue.  (I sometimes add a cool yellow to this to make the color even greener.)  This color also makes lovely greys when mixed with tints of red or orange.

What about Manganese Blue, once used for swimming pools and achingly reminiscent of Caribbean waters?  Mining the mineral for this color was an environmentally toxic process and has stopped.  According to Robert Gamblin of Gamblin Artists Colors, the last industrial batch of this pigment was made in 1989, and he worked hard to create a "hue" that closely matched the original.  (Robert once gave me a rare tube of genuine Manganese Blue to play with and, honestly, I prefer the "hue" he makes.  Genuine Manganese weakens too easily.) 

And, finally, what about Phthalo Blue?  This intense pigment is great in pastels, providing a beautiful range of intense darks and tints.  But it's a lot like nitroglycerin (or maybe Brylcreem), where "a little dab'll do ya."  Powerful stuff, it's best avoided in oil and acrylic paints.  I used to have both it and Phthalo Green on my palette, and to this day I regret the messes it made.  Prussian Blue is a better choice than Phthalo Green.  Intense and staining, yes, but not like Phthalo Blue.  Plus, Prussian Blue, Yellow Ochre and Burnt Sienna make a wonderful three-color palette for landscape painting.

I'm including below an image of swatches I've made of colors from Gamblin.  You can learn more about their line of colors here.  They also have a series of informative articles about the color experience here.

Masstone, Drawdowns, Undertone, Tints and Shades

Top: Masstone/Drawdown/Undertone
Bottom:  Shade/Tints
L-R: Prussian Blue, Phthalo Blue, Indanthrone Blue, Cobalt Blue, Ultramarine Blue

Top: Masstone/Drawdown/Undertone
Bottom:  Shade/Tints
L-R: Cobalt Teal, Cerulean Blue Hue, Cerulean Blue, Manganese Blue Hue, King's Blue (Williamsburg), Sevres Blue (Williamsburg)

Here are color swatches from Gamblin's website, showing some of the colors as tints, tones and shades.  Also, if the color is transparent, there is a glaze. Tint is made with Titanium Zinc White + the color, tone is  made from Portland Grey Medium + the color, and shade is made from Chromatic Black + color. The glaze swatch is made with Galkyd medium. 













Sunday, January 29, 2023

New Blog Series on Color, Part 5: Violet

View in browser

Violets/Purples from Gamblin Artists Colors


Violet lurks everywhere in the landscape.  It inhabits the deep shadows; but it also sparkles in sunlit rock, adding a refreshing cool note to a warm subject.  In my split-primary palette, I can sense it buried deep in Ultramarine Blue, and by adding a little Alizarin Crimson, I can bring it to the surface.  And if I want an even stronger note, I can add Dioxazine Purple—or one of the many other violets available—to my palette.

HISTORY

You've most likely heard of Tyrian Purple, a brilliant pigment loved by the Roman emperors and famed for its expense.  Over 10,000 whelks are needed to make a single gram; you can still buy it today, with a gram going for $4000 from Kremer Pigments.  But it's not just expensive—it's also incredibly fugitive.  A cheaper purplish earth color, perhaps used by the lower strata of Roman society, is Caput Mortuum ("dead head" or "worthless remains" in Latin), a pigment derived from hematite.  But it wasn't until 1859 that a truly rich, lightfast and inexpensive violet became available with the creation of Cobalt Violet.  Early versions were poisonous and made from ore containing arsenic. In 1868, chemists developed the non-toxic Manganese Violet.  In our modern era, a whole host of organic (carbon-based) violet pigments, such as the dioxazine and quinacridone colors, were developed.

(Side note:  What's the difference between purple and violet?  Purple is a combination of red and blue pigments; violet occupies a range in the electromagnetic spectrum.  Many artists, however, use the terms interchangeably.  Since I consider my palette to be spectrum-based,  I use the term "violet.")

USAGE

You don't often think of violet as being a landscape color.   But consider:  It's not primary colors but secondary colors that make up the natural landscape.  Orange, green, violet—all of these appear in vegetation, from warm orange in sunny spots to cool greens in the half-tones to even cooler violets in shadow.  Orange and green might seem obvious to you; violet, perhaps less so.  But believe me, a little touch of the right violet in a landscape adds punch.

And what is the right violet?  Usually, "right" has to do with color temperature and intensity and the relationship to surrounding colors.  I can adjust the temperature of violet with hues near it on the color wheel.  For example, if I want my Dioxazine Purple warmer, I can mix in a little Alizarin Crimson, which is closer to red.  If I want to cool it down, I can add a little Ultramarine or Cobalt Blue.  If I want to reduce the intensity, I can add a bit of a complement (a yellow) or near-complement (yellow-green or yellow-orange.)  Violet, by the way, can make some very beautiful greys with near-complements and white.  And I can make a really dark, transparent neutral by mixing Dioxazine Purple and Phthalocyanine Green.  Sometimes you want black without using an actual black.

Violet has always been another of my favorite colors in pastels--warm violets, cool violets, intense violets, dull violets.  I find them especially useful in the greens, deepening shadows or de-intensifying light areas.

I'm including below an image of swatches I've made of colors from Gamblin.  You can learn more about their line of colors here.  They also have a series of informative articles about the color experience here.

Top row: Tints
Bottom: Masstone + Undertone
L-R: Quinacridone Magenta, Quinacridone Violet, Manganese Violet, Cobalt Violet, Dioxazine Purple, Ultramarine Violet
(I included the Quin Magenta because it is so close in hue to the Quin Violet)

Here are color swatches from Gamblin's website, showing some of the colors as tints, tones and shades.  Also, if the color is transparent, there is a glaze. Tint is made with Titanium Zinc White + the color, tone is  made from Portland Grey Medium + the color, and shade is made from Chromatic Black + color. The glaze swatch is made with Galkyd medium. 







Sunday, January 22, 2023

New Blog Series on Color, Part 4: Red

View in browser

Reds from Gamblin Artists Colors

As a plein air painter, I tend to avoid bright reds—they usually have too much "punch" for the natural landscape.  Instead, I tend toward the more earthy reds like Burnt Sienna and its cousins.  Bright reds are rare in my world.  When I'm painting in the area around my seaside studio in the Canadian Maritimes, I only find bright reds on lobster boats and lighthouses.  More common are the pale pinks of the beach rose, which tend to be rather dull.  (And for them, I prefer to use Quinacridone Magenta, which keeps some of its intensity when used as a tint.) Out in the Southwest, which many people think of as being filled with such bright color that the landscape seems nearly incandescent, the reds actually are still quite muted.  For example, Sedona is famous for its red rocks, but they appear so vibrant only because of the juxtaposition of vegetation and its complementary greens.  Pick up a rock at your feet and examine it carefully, and you'll see how dull it truly is.

On the other hand, when I'm the studio, I sometimes do push the intensity of red for effect.  I might use pure Cadmium Red Medium in large swaths of sunlit rocks—and as dark as that pigment is, it really does look like it's being hit by strong sunlight.  (I'll confess, I do this sometimes in the field, too; I'm not such a literalist.)

HISTORY

Red is one of the first colors early humans dug up to daub on cave walls.  Early cave paintings—some 40,000 years old—were made with hematite and other earth reds.  Although most earth reds are dull, another ancient pigment, cinnabar, is very intensely colored.  The fact that it contains toxic mercury didn't stop alchemists in the Middle Ages from valuing it as essential in their search for the philosopher's stone.

During the 13th century, alchemists accidentally created artificial cinnabar—vermilion.  Vermilion, like cinnabar, is also toxic and changes color upon exposure to the lead in lead white, another common pigment at that time.  Red lead is a little better when used with lead white, but just like cinnabar and vermilion, it is toxic and prone to changing color over time when exposed to air.

These pigments were the only intense reds available until the creation of the "lake" reds such as madder in 1804.  Even so, the lake reds, not actually made of pigment but of dyes fixed with a mordant, have a big problem—they are notoriously fugitive.  Alizarin Crimson, another fugitive color derived from madder, was synthesized in 1868.  But the problem of lightfastness wasn't truly solved until Cadmium Red was created in 1907.  Soon to follow were a whole host of intense, lightfast organic (carbon-based) reds like the napthols and perylenes, which also have the advantage of being non-toxic and cheaper than cadmium colors.

USAGE

For my split-primary oil palette, I like Napthol Scarlet and Permanent Alizarin Crimson.  Napthol Scarlet is warm and semi-opaque while Alizarin is cool and transparent, and together they give me a wide range of temperatures and opacity.  I've played with other reds—the cadmiums, of course—and some the other organic colors.  I tried Napthol Red but found it cooled down too much when added to white; Napthol Scarlet is a bit warmer and seems to hold the heat a little longer.  

Lately, I've been playing with a limited earth color palette that uses just one red—Burnt Sienna— plus Yellow Ochre and Ultramarine Blue.  Burnt Sienna, a dull red, makes beautiful browns and greys when used with the other two colors.  In pastel, some of my favorite colors are the dull reds.

I'm including below an image of swatches I've made of colors from Gamblin.  You can learn more about their line of colors here.  They also have a series of informative articles about the color experience here.

Images below include draw-downs, tints and shades:

Gamblin Earth Reds:
Indian Red, Burnt Sienna, Venetian Red, Transparent Earth Red

Gamblin Mineral Reds:
Alizarin Crimson, Permanent Alizarin Crimson, Cadmium Red Light, Cadmium Red Medium, Cadmium Red Deep

Gamblin Organic Reds:
Napthol Scarlet, Napthol Red, Perylene Red, Quinacridone Red, Quinacridone Magenta, Brown Pink

Here are color swatches from Gamblin's website, showing some of the colors as tints, tones and shades.  Also, if the color is transparent, there is a glaze. Tint is made with Titanium Zinc White + the color, tone is  made from Portland Grey Medium + the color, and shade is made from Chromatic Black + color. The glaze swatch is made with Galkyd medium. 
















Sunday, January 15, 2023

New Blog Series on Color, Part 3: Orange

View in browser

Oranges from Gamblin Artists Colors

Orange is a color I don't use much unless I need a pure orange note, such as I can get with Cadmium Orange.  Most often, I just mix orange out of Cadmium Light and Napthol Scarlet or some other yellow/red combination.  For pastel, I do use orange, but most often the duller versions that tend toward brown; I have some lovely dull tints that are just right for highlights on sunlit rock planes or dry grasses.  Bright orange isn't a color I see often in a landscape, unless it's flowers or some man-made element.

HISTORY

One doesn't think of orange as a color derived from earth pigments, but some of the ochres possess a decidedly orange cast.  The ancients made use of realgar, a mineral that can be red but also orange.  Realgar is an incredibly poisonous arsenic compound—and it's usually found in ores right beside the equally-toxic orpiment, which I discussed in my post on yellow.  (The ancient Chinese, interestingly, called realgar "masculine yellow" and orpiment, "feminine yellow.")  Realgar was once used to kill weeds and rodents.  So yes, it is that toxic and why we don't paint with it today.

In 1809, chemists invented Chrome Orange.  Cheaper and less toxic than Realgar, this lead compound is rather fugitive.  Fortunately, a more lightfast (but still somewhat toxic) pigment, Cadmium Orange, became available after 1840.  The Impressionists used both of these oranges.  Finally, late in the 19th century, chemists discovered organic (carbon-based) pigments that are richer and more permanent and possess a greater tinting strength than any earth or mineral pigment.  Today, we have orange pigments such as monoacetolone that maintain their richness in thin glazes and also mix in beautiful ways with other colors.

USAGE

As I mentioned in an earlier post, on my palette I have two yellows and two reds.  If I  mix a cool yellow with a cool red, I get a much cooler orange than if I mix a warm yellow and a warm red—two very different oranges that can be used in different ways.  If I want a brighter orange, I would use one of  three oranges from Gamblin:  either the mineral-based Cadmium Orange or the carbon-based Permanent Orange or Transparent Earth Orange.   If I'm painting a cityscape, I might want to use Cadmium Orange or Permanent Orange (mixed with a little white to increase opacity) in warning signs or traffic cones.  I might use Transparent Earth Orange for toning a white canvas.  This makes a great alternative to Burnt Sienna or some other warm but opaque earth pigment; a tone of Transparent Earth Orange almost glows like stained glass.

I'm including below an image of swatches I've made of colors from Gamblin.  You can learn more about their line of colors here.  They also have a series of informative articles about the color experience here.

Oranges: Tints, Drawdowns and Shades
Top row, tint.  Bottom row, shade.  Between, drawdown.
L-to-R: Transparent Orange, Transparent Earth Orange, Permanent Orange, Cadmium Orange, Cadmium Orange Deep.

Here are color swatches from Gamblin's website, showing some of the colors as tints, tones and shades.  Also, if the color is transparent, there is a glaze. Tint is made with Titanium Zinc White + the color, tone is  made from Portland Grey Medium + the color, and shade is made from Chromatic Black + color. The glaze swatch is made with Galkyd medium. 







Sunday, January 8, 2023

New Blog Series on Color, Part 2: Yellow

View in browser

Yellows from Gamblin Artists Colors


As a plein air painter, I use yellow often—but very little of it "right out of the tube."  Unless I'm painting brilliant, sunlit autumn foliage, intense yellows like Cadmium Yellow Deep need to be dulled down, usually with a complement or near-complement.  (By the way, Gamblin's series of Portland Grays are wonderful for this.)  But already-dulled yellows, such as Yellow Ochre and Naples Yellow, do work well "right out of the tube," as they make up a great deal of the dull color in the Southwest landscape I inhabit.

HISTORY

Before the Industrial Age, the only yellows available were mined from the earth.  The ancient Egyptians used Yellow Ochre to paint the skin tones on their murals.  Naples Yellow was used by the Babylonians in ceramics.  (The genuine version is a toxic lead compound; these days, many artists use the "hue" which is usually a mixture of Yellow Ochre, white and a red.)  One yellow you don't hear of much is the also-poisonous Orpiment (arsenic sulfide), which the Chinese used for illuminating manuscripts.  Gamboge, which was not mined but harvested from solidified tree sap, was used in glazing.  Indian Yellow replaced Gamboge in the mid-19th century.  True Indian Yellow, which is no longer available, is said to have been made in India from the bladder stones of cows fed on mango leaves.  (Recent research indicates this isn't true.)

The 19th century saw the advent of mineral colors, such as Chrome Yellow, which was used by Van Gogh and Seurat.  This toxic pigment (lead chromate) was quickly replaced with another, Cadmium Yellow (cadmium sulfide), around 1840.  You might wonder why cadmium, which is also poisonous, replaced Chrome Yellow.  While Chrome Yellow discolors quickly and has a low-tinting strength, Cadmium Yellow remains bright and enjoys greater tinting strength.  Monet used it in his paintings.

Finally, in modern times, organic (carbon-based) pigments were developed.  Hansa Yellow, which was first made in pre-World War I Germany, is very similar to Cadmium Yellow, except that it's transparent, brighter and non-toxic.  Also, a little goes a long way, thanks to its greater tinting strength.  It's also cheaper than Cadmium Yellow and weighs less per ounce, which is important to the plein air painter.

USAGE

In my workshops, when discussing palettes, I usually get the question:  What's better, a hue or the genuine article?  "Hue" doesn't necessarily equate to "student quality."  There are a couple of reasons why you might use a hue rather than the genuine pigment. Sometimes the genuine pigment is toxic, as in the case of Naples Yellow.  Or it's expensive, as in the case of Cerulean Blue.  (Yes, I know my post is on yellows.)  Or, sometimes it's no longer available, as in the case of Manganese Blue, which is no longer mined because of environmental concerns.  In all three of these examples, the hue versions are perfectly fine and often superior.

Thanks to modern chemistry, we now have an abundance of yellow pigments to work with.  When I'm painting outdoors, I usually use Cadmium Yellow Light, Cadmium Yellow Deep, Yellow Ochre and, sometimes, Naples Yellow Hue.   The two cadmium yellows are great for flowers in the field and autumn foliage, but as I mentioned earlier, I usually knock these down in intensity with a little complement or near-complement.  For this I typically use Ultramarine Blue with a dab of Permanent Alizarin Crimson or just Gamblin's Portland Gray Light.  Yellow Ochre and Naples Yellow I might use straight out of the tube for exposed rock.  If I have to lighten either of these more, I also add a touch of Cadmium Yellow Light to raise the intensity; white tends to cool and dull color.  I also sometimes add a touch of Naples Yellow Hue to my Titanium-Zinc White to increase the overall warmth of my lights.

And what about pastel?  As I mentioned in my post about my palette, I have both warm and cool yellows, in a variety of tints and shades.  The tints tend to lose intensity unless the manufacturer knows what he's doing; the shades always tend to brown.  It's almost impossible to get a dark, rich yellow that isn't brown.  Yellow really just wants to be light.  (I won't be talking about pastel much or at all in this series. With pastel, what you see is what you get.  The only concern is whether the pigments used are lightfast or not.)

I'm including below an image of swatches I've made of colors from Gamblin.  You can learn more about their line of colors here.  They also have a series of informative articles about the color experience here.

Gamblin Yellows
Top (l to r): Nickel Titanate Yellow, Cadmium Chartreuse, Cadmium Lemon, Cadmium Yellow Light, Cadmium Yellow Medium, Cadmium Yellow Deep
Middle: Radiant Yellow, Radiant Lemon, Hansa Yellow Light, Hansa Yellow Medium, Hansa Yellow Deep
Bottom: Indian Yellow, Naples Yellow Hue, Yellow Ochre, Gold Ochre, Transparent Earth Yellow

Here are color swatches from Gamblin's website, showing some of the colors as tints, tones and shades.  Also, if the color is transparent, there is a glaze. Tint is made with Titanium Zinc White + the color, tone is  made from Portland Grey Medium + the color, and shade is made from Chromatic Black + color. The glaze swatch is made with Galkyd medium.