Category Archives: Painting Materials

Pyrocumulus

People here in Sacramento, California, learned a new word last week: “pyrocumulus.” It’s a type of cumulus cloud that can form over a wildland fire when conditions are right.  Well, conditions were right on September 17 when the King Fire more than doubled in size in one day.  (It’s called the King Fire because it started near King of the Mountain Road in Pollock Pines, about 60 miles east of Sacramento.)

Pyrocumulus sketch ©2014 Stephanie Benedict
Pyrocumulus. ©2014 Stephanie Benedict. 3 in x 5 in., gouache. Stillman & Birn zeta sketchbook. This is how the cloud looked to me from about 50 miles away in suburban Sacramento.

The Wikipedia definition of a pyrocumulus is:

produced by the intense heating of the air from the surface. The intense heat induces convection, which causes the air mass to rise to a point of stability, usually in the presence of moisture…

Pyrocumuli contain severe turbulence, manifesting as strong gusts at the surface, which can exacerbate a large conflagration. A large pyrocumulus…may also produce lightning. A pyrocumulus which produces lightning is actually a type of cumulonimbus, a thundercloud, and is called pyrocumulonimbus.

One person from Calfire said in a news report that the clouds can collapse quickly, too, sending embers out in several directions.

Conditions in the Sierra Nevada foothills are so dry, after three years of drought and almost no snow last winter, that the fire just took off, increasing from about 28,000 acres to over 70,000 acres in one day. The winds shifted in the days after the pyrocumulus, slowing the fire’s expansion and sending smoke out over the Sacramento Valley and the foothills.  Still, in less than a week the fire burned more than 80,000 acres (or 120 square miles) of forest, as well as a number of homes.

After decades of fire suppression in California, the forests are thick with brush (where they haven’t been clear cut). It will take crews from Calfire and the US Forest Service weeks to put this fire out. The worst part?  The fire was apparently deliberately set.  A man has been arrested for arson.

Fire is part of the natural cycle in California. People who live in the foothills know it could happen in any year, dry or no.  And we could manage the forests better, leave the oldest trees, which are most fire-resistant, and either burn or cull the understory more.  The forests used to burn every decade or so.  But we can’t really let these fires burn now—there’s too much fuel.  Just like the King Fire.

Do we also have climate change? I think so, though no one can say for sure yet.  National Geographic speculated on this recently.

Have you been affected by fire in the West? Have you seen a pyrocumulus cloud?

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Reboot!

My goodness, but I’ve been away from this blog a long time!

Vernal Pool sketch by Stephanie Benedict
Sketch for Vernal Pools. ©2012 Stephanie Benedict. 3″ x 4″ graphite.  I do love water-soluble graphite!

I learned a powerful lesson about the need for systems this year. Having good systems will support you in your whatever you do, from having an organized computer and file system, to building supportive habits of writing, drawing, or whatever it is you do. I fell away from writing at first because my computer decided to stop working, and had to be replaced. That meant recreating my old hard drive, re-installing software. (But of course nothing works quite the same. I would like to request that you software developers out there not fix things that aren’t broken.) And then I just got busy and never got back to posting.

So—I’m rebooting this blog. I intend to post approximately weekly, and to write about nature, painting, and painting (and drawing) nature. I hope you find something interesting here, and perhaps even learn something!

Something Completely Different

I’ve been experimenting with caseins recently. I got some after I read the amazing James Gurney’s posts and watched his videos about the paints. (I rather wonder how much sales of caseins spiked after he blogged about them.) They’re fun!Toy Tiger ©2013 Stephanie Benedict. 5: x 7". Casein

Toy Tiger ©2013 Stephanie Benedict. 5: x 7″. Casein heightened with watercolor and water soluble pencil. On panel.

They’re a bit like gouache, in that they are an opaque, water-soluble medium, but they seem to me more flexible. You can thin them to do washes, or use them fairly thickly. They dry to a soft matte finish. But they’re also sort of like oil, in that you can mix them wet-into-wet if you work quickly. Gurney calls them “oils on steroids,” but I’m not sure I agree. I think they’re more like gouache on steroids. But they also share a feature of acrylics: they change value once dry, generally turning darker. Since values are something I struggle with, and therefore focus on, I find the value shift annoying.

But, not enough to stop me from playing more with them!

Posting will be intermittent the next few weeks. I’m trying to finish up some larger pieces for a show, and to get ready for some trips.

Why I’m not (really) a Plein Air Painter

I love to do underpaintings. I love that first layer, the first block-in, the first color on the canvas. Maybe it’s because I know that whatever I do doesn’t have to be either precise or perfect, so there’s a huge amount of freedom with first layers.

 

Fall reds and greens, underpanting
Sometimes I do underpaintings in acrylics, sometimes oils. For this one, I used Gamblin’s fastmatte paints, just to try them. I’m not sure I like them yet. When this is dry, I’ll work in regular oils to add at least one, perhaps several, more layers.

And when one paints en plein air, of course, they’re really painting alla prima, or all in one sitting. From start to at least pretty close to finished. Oh, it’s true, you can return to the same spot a day or few days later to finish something up, for example, on a larger canvas. Or you can be like John Singer Sargent painting Carnation, Lily, Lily, Rose, and get everything set up to allow you to paint for those few minutes around sunset when the light is perfect—and make your models do this for months. That is, you can return more than once if the weather holds. A day or two after I was at the park shown above, we got three huge storms that changed the scene completely. All those bright red leaves are gone.

Or, you can be like me and do little studies outdoors and then do larger pieces in the studio.

I’d love to say I was a better plein air painter than I am, but I’m not.

And this is probably why: I like to paint in layers.

 

Working on a Toned Ground

Here’s a trick I learned from Kathleen Dunphy: I tone my canvas yellow before I paint on it.

Many artists over time have worked on toned grounds. (The “ground” is the surface one paints on.) The white of a bare canvas is just too intimidating or too harsh, so painters tone the canvas with a thin layer of color.

Pine Tree Study by Stephanie Benedict
A plein-air study of two pine trees in snow. The right-hand side shows the yellow-toned ground. I toned this panel with a thin layer of gesso tinted with Hansa yellow medium acrylic paint.

A Modern Approach

The traditional color for toning canvas is raw sienna, which will give the canvas a warm, slightly orange-y color. I’ve tried that, and it’s OK. Others use burnt umber or red or a mixture of colors.

After I began studying with Dunphy in 2008, I explored a number of options: raw sienna, quinacridone burnt orange (which is like raw sienna only brighter), neutral gray, burnt umber. Eventually I came to agree with Kathleen: I like yellow the best. So now I tone all my canvases with a pale wash of cadmium yellow light or Hansa yellow before I paint.

Now, too much yellow can be a distraction at first, and make it hard to judge the relative color and value of the first paints I put onto the canvas. But the payoff is huge: the yellow gives an underlying warmth to the canvas, which complements cool paintings on cloudy days and highlights the warmth of sunny days*.

 The Process

The traditional method is to thin a little bit of oil color into a lot of solvent and wash it onto the canvas either with a brush or a rag. Then you have to let it set up before you start painting.

A more modern way is to use a bit of acrylic paint thinned with water and wash it onto the canvas with a rag. But the representatives at Gamblin Colors (which makes oil paints and mediums) convinced me that perhaps that’s not the best method, so most recently I’ve started adding a touch of yellow acrylic paint to white gesso, and adding a layer of colored gesso. I typically use pre-primed panels or canvas, so my colored layer doesn’t need to be thick or completely covering: I’m not trying to build a whole new ground. And I can make the yellow then very pale. Yes, it takes a bit of planning, but I like the results.

What do you think?

If you’re a collector, can you tell if your paintings have toned grounds? If you’re an artist, do you tone your canvas first?

*I’m not sure this would work for the painter who works in the Henry Hensche, full-spectrum colorist style. In that style, that extra warmth might conflict with the finished painting. But with a more limited palette, it works just fine.