Loni writes ….. Since the borealis happens only at night and for me to capture the effect of that…… Would you start out with a black canvas? The sky is almost black (midnight blue) to be precise, only the borealis is lit up and brings the landscape to a almost daylight Hugh also the reflection in the lake is quit dark, and the trees in the back ground are most definitely black. And if I start out with a black canvas can I bring the borealis colors which are very light yellow, orange and pink on the horizon and neon green throughout the sky, to that color?
To answer this question, I’d like to first explain what is an Aurora Borealis (Northern Lights) and what is their cause. The Aurora Borealis is named after the Roman goddess of the dawn, Aurora, and the Greek name for north wind, Boreas.
Let’s look at the sun whose energy production is far from even and fluctuates on an 11 year cycle. Maximum production coincides with high sunspot activity when processes on the sun’s surface throw particles far out in space. These particles are called the solar wind and cause the Aurora Borealis.
The sun’s surface temperature is approximately 6,000 0C, much cooler than the interior which is several million degrees. In the sun’s atmosphere or corona, the temperature rises again to several million degrees. At such temperatures, collisions between gas particles can be so violent that atoms disintegrate into electrons and nuclei. What was once hydrogen becomes a gas of free electrons and protons called plasma. This plasma escapes from the sun’s corona through a hole in the sun’s magnetic field. As they escape, they are thrown out by the rotation of the sun in an ever widening spiral – the so-called garden-hose effect. The name originates from the pattern of water droplets formed if we swing a garden hose around and around above out heads. That’s why the Northern Lights look like lines of light to us, or if you will lines disappearing into the horizon.
In summary, an Aurora Borealis is an electro-static phenomenon, characterised by a bright glow and caused by the collision of charged particles in the magnetosphere with atoms in the Earth’s upper atmosphere. Auroras are usually observed in the night sky, particularly in the polar zone. Some scientists therefore call them “polar auroras” (or “aurorae polaris”). The aurora borealis most often occurs from September to October and from March to April and predominantly occur the arctic and antarctic regions. In certain spots the auroral displays are numbered as high as 200 annually whereas others are as low as 20 per year.
I’ve always painted Northern Lights using a dark canvas so I can really accentuate the colors of the aurora borealis. I layer the colors I want to use within the Aurora Borealis directly onto the blank canvas in the area where I will paint the Northern Light in the sequence I want those “lights” showing. I typically use Indian Yellow. Alizarin Crimson, (the overlap of these two colors will form orange) and Pthalo Green. I then paint the rest of the sky with Prussian Blue. Also the surface below the horizon is painted with another color, i.e. Prussian Blue.
After these transparent colors are applied, my canvas still looks pretty much like a dark canvas. With a fan brush, loaded with a very dirty white paint, I’ll draw the first garden hose Aurora Borealis line. Then using a large brush, I’ll pull this color up and then I’ll pull it down. Wipe the large brush dry with a paper towel, than using quick horizontal strokes go across the garden hose Aurora Borealis line as though you were blending a reflection in water.
Draw the next line with your fan brush and repeat the big brush procedure just described in the previous paragraph. I generally have two or three Aurora Borealis lines in my paintings.
As you paint the rest of your scene, bear in mind that most Northern Lights appear during Fall or Spring, so don’t be prone to just painting winter scenes with these beautiful lights.
Hope this helps.