Outdoor Theory: Lighting

Putting the sun at your back at sunset or sunrise creates a front-lighting condition. Looking into the sun at these hours can create a rim or back-lighting condition. Most other hours will produce form-lighting. 

The sun and the moon are directional point sources of light. Like an indoor incandescent light, they are (in practice) smaller than the subject they illuminate and create cast shadows. The sky on the other hand is a non-directional diffused source of light, larger than the subject and illuminating from all directions at once. Instead of casting sharp-edged shadows, a gray day creates penumbras, soft-edged shadows that gradually get darker as they get closer to the object casting. When the sun breaks out on an overcast day, the shadows don't get darker, the lights get lighter.

Some observations to consider under different outdoor lighting conditions.

Detail from the above highlighting the difference between a point light source and a diffused light source.

© John Ennis 2011

Next Topic: Sunlit color

Outdoor Theory: Planes

Seeing the complex forms in nature as simple, basic planes is helpful in assigning relative values accurately to each item. This in turn helps give your landscape a natural look. The top of this page points out the relative difference between the basic planes. The ground becomes the top plane, receiving the most light. The slanted plane represents the hillside, and because of it's angle receives less light and consequently is one value darker than the top plane.  The trees represent the upright plane, receiving even less light and is therefore 2 values darker than the ground in the light. Translating this into painted values, the grass in sunlight is painted at 8th value, and in the shade at value 6. The upright plane (tree) becomes 6 in the light and 4 in the shade.

© John Ennis 2011

Next Topic: Outdoor Theory: Lighting

Outdoor Theory: Sky Vault

The sky is a vaulted arch of diffused light encompassing the landscape. It illuminates our scene evenly as a blueish light-source on a clear day (or a gray light-source on an overcast day). If you go outside and look up, you will see the zenith of the sky vault which can get as dark as value 7. If you could follow the sky vault to the horizon, it will gradually lighten to value 9.5. In practice, your landscape will encompass only a small window of the sky vault.  The picture zenith (below) is decided by your composition, and the range of value in the sky vault of your actual painting may be as little as 8th value at the top to 9th value above the tree line.

Another way of visualizing this concept below. The sky arching over the landscape with values from the horizon at 9.5 to 8 creates ambient light for the shadows. The sun adds more light creating distinct light and shade differences. A good generality to remember is that outdoors there is an approximate 2 value difference between light and shade compared to indoor lighting that has an approximate 5 value difference.

© John Ennis 2011

Next Topic: Outdoor Theory: Planes

Basic Days

Top: Sky-lit or Gray day. Left: Sun & Sky. Right: Moon & Sky.

Gray Day
On a gray (or sky-lit) day the entire sky becomes a large diffused light source illuminating the landscape from the top down in a soft, gradual, nearly flat light. In these models, Reilly has assigned a local value to each picture element. The sky being the light source is the lightest at value 9. The road, locally lighter than the grass is the next lightest at value 7, followed by the grass at 6. The hillside is value 4, and the tree is also value 4. It's important to consider the gray day because this lighting helps establish the home or local values of the elements of your picture.

Gray day value study. 2011 E. Anzini

Sun & Sky
When the sun, a point light source, shines its light it brightens a landscape already illuminated by the sky. It creates a distinct light and shadow side to the objects. In this lighting, the tree remains the same in the shadow as it did overall on a sky-lit day at value 4. However, the sun-lit light side of the tree now jumps to value 6. Likewise, the grass illuminated by the sky was 6 overall on a skylit day, and is now value 8 in the light and 6 in the shadow. Its really important to understand that a sunny day is a skylit day with sunlight added.

Sunny day value study. 2011 E. Anzini

Moon & Sky
A moonlit landscape is similar to a sunny day, in that a weak point light source, the moon, lights the landscape creating light and shadow albeit with soft edges. The values of course are dampened, and the sky offers little or no secondary illumination, so the shadows go very dark.

 Moonlit value study. 2011 E. Anzini

© John Ennis 2011

Next Topic: Outdoor Theory: Sky Vault

Painting Outdoors: Introduction

Student color note

Each summer, Frank Reilly took a number of his students to the Art Students League campus in Woodstock, NY to teach outdoor painting. According to alumnus Jerry Allison, "Studying landscape painting in Reilly's Woodstock classes was a grand adventure." Beginning in the 1940's and through the mid '60's when the Art Students League's 100-year lease ran out, his students spent the summer in Woodstock and participated in a 12 week immersion program that included landscape painting, and indoor and outdoor figure painting. 

Summer Program

Below is a roster from one summer (1949 or 1950) that includes landscape artist Clark Hulings, illustrator and portrait painter Bob Berran, and painter, author and teacher George Passantino who took over the morning Reilly class at the League when  Robert Schulz passed away in the late 1970's. Also on the roster are Jack Faragasso who continues to teach Reilly's methods at the League, and illustrator Larry Newquist. Students were on their own to find housing, but the town, already a summer tourist destination, was welcoming to the aspiring painters.

Summer roster, circa 1949-50

Frank Reilly and students

Studio at Woodstock, NY

© John Ennis 2011

Next Topic: Basic Days

Lighting Basics

This post on lighting was borrowed from the Light & Shade section, which I hope to get to eventually. Reilly refers to these basic lighting conditions through out all aspects of the program, so I think it's important to add it now. I will return to this topic in more detail at a later date.

There are four basic lighting conditions to consider. Front Lighting, Form Lighting, Rim Lighting and Back Lighting.

Front Lighting:

In this lighting condition there is no shadow to help give us the illusion of form. It shows minute detail and local values well. This is perhaps the most challenging and least used lighting condition for painters.

Form lighting:

As its name implies, this lighting condition helps us define the illusion of three dimensions by giving us a light side and shadow side to create form. It is our best option for showing three dimensions. Typically three-quarters to two-thirds of the subject is illuminated by the light.

Rim Lighting:

In this lighting condition, the subject is three-quarters in the shadow and one-quarter in the light. The light is actually coming from behind the subject, creating a brilliant light. The lights are compressed within a two value range, typically between 8th value and 10th value, so the changes in the light are hard to determine. Most of the modeling is done in the now expanded shadow value range. Good for dramatic effect.

Back Lighting:

Similar to Rim Lighting but with out the edge light. Also good for drama. Be careful of over modeling.

This post concludes the painting section of Reilly's program for the time being. This section focused primarily on  indoor figure-painting. I've covered the essential topics, and may add a few things in the future. Since summer is beginning I want to start blogging the landscape part of the program.

© John Ennis 2011

Next Topic: Landscape program

Effect of Colored Lights

The color of the light source directly affects the hue on the light side of form. Within the cast shadow, it causes the illusion of the light-source complement. As Reilly illustrates in his notes below, a red light on a white object would give the white a red cast in the light, and the cast shadow would look like blue-green. 

Paint the object in the light with it's local color plus the color of the light source. 


The cast shadow is the local plus the complement. It's chroma should only be half as strong as the surrounding light area.


The chroma in the cast shadow gets slightly weaker as it comes towards the viewer, and stronger as it recedes from view. 


© John Ennis 2011

 Next Topic: Lighting Basics