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

Color Vibrations

Claude Monet  "The Four Trees"  www.metmuseum.com

Reilly's original notes are missing on this topic, so I am substituting my own from the Faragasso class. Color Vibration refers to the readjustment of flat color for enhanced effect. A visual mixture of color that still represents the average. Think Impressionism or Pointillism. A flat area of color can be made more interesting by adding brushstrokes of neighboring hues, values or chroma to create a more interesting and painterly effect.

Initially try changing only a single factor, like splitting the hue. By painting red and yellow brush strokes of the same value and chroma alongside each other they blend visually to make yellow-red (orange). Or instead split the value: by painting yellow-red brushstrokes of equal chroma at lighter and darker values alongside each other they average out to the original value with a more exciting result. You can increase the variety of factors, and the degree to which you change them.


By now reading Munsell notations should be second nature to you. YR5/5 means yellow-red, 5th value, 5th chroma.

Adding more variations of color adds more interest. Be aware that the more more factors you change and the greater degree to which you change them, the harder it will be to maintain the average color you began with.

© John Ennis 2011

Next Topic: The Effect of Colored Lights

Gradations and Progressions

Gradation: 

Reilly uses the term gradation to describe a gradual change in value over a flat surface; side to side, top to bottom or diagonally, notably on the background. It is a minor effect of light and can help show the position of the light source, and how far the subject is from the background. 

The nearer the light source to the background, the greater the degree of gradation.

Keep the degree of change modest, or the background will begin to look three-dimensional and detract from the form of the subject. Think of gradation as both a natural effect and a design element.

Progression: This term describes the degree of change in a form as it progresses out from the picture plane towards the viewer or recedes away from the viewer. The greater degree of change, the more attention it will receive, and the more it will appear to project toward the viewer. Conversely, the lesser degree of change the more the object will seem to recede. Hard edges help an object project, soft edges help it recede. High value contrast help it to project,  minimal contrast helps it to recede.  Reilly emphasizes that the changes in value should be made to the object, not the background.

© John Ennis 2011

Next Topic: Color Vibrations

Basic Planes

By simplifying form into planes, it becomes easier to understand and see how light affects form. There are four basic planes: front or upright plane, side(edge) plane, top plane, and under plane.

Top planes in the light

Always go 1 value higher than average 

More neutral than the average

Picks up the hue of the light source (e.g. in north light would shift towards blue)
Use hard edges

Under-planes in the light -

1 half value darker than average 

1 & 1/2 value darker than the top plane

Soft edges

Avoid going too dark

Top planes in the shadow 

1/2 lighter than average in the shadow

Soft edges
Can be more neutral

Under-planes in the shadow 

One half value darker that the average in the shadow
Can be illuminated by reflected light resulting in hue, value and chroma changes

No hard edges, edges  are soft all over

It is the angle that the plane presents to the light source that determines its value.

Translate the idea of planes back into painting form.

The Edge Plane:
The front plane is usually more chromatic than the side plane, especially with skin. The edge plane drops slightly in value and chroma as it bends away from view, due to the texture of the skin containing pores and hair follicles. This can be exaggerated when necessary. A shiny surface might produce a different result, where reflected light might increase the chroma.


© John Ennis 2011


Next Topic: Progressions & Gradations

The Effect

Rembrandt (Rembrandt van Rijn)  Self-portrait  www.metmuseum.org

In Reilly's words, "The effect is where you look first, it is where you want the viewer to look. It is a guided tour that is planned by the artist, the looking device used by the Masters."

Reilly used the term "The Effect" to describe how the effectiveness of light on the subject can be used to the artist's advantage. By emphasizing the position and brilliance of the light source, the viewer's eye can be directed to a chosen area of interest. Exaggerate this principle from the beginning. Include it in your color note.

Look for it in the area nearest the illumination, the largest, lightest area of the form. The plane that faces the illumination. In life class this might be the upper chest of the model, but depending on the light source it could also fall on the hips, shoulder, head, etc. Consider it an element of design that increases form and volume to the subject. Think Rembrandt! 

It is most often a value problem. Within the light area there is a concentration of light due to the bending away of light. A light source creates a cone of light whose strongest illumination is in the center, allowing a gradual fall off. This concentration of light creates an area in the light which is lighter in value than other areas in the light, thereby creating even more contrast with the shadow. A focal point created by illumination. To make this effect of light work, create the greatest contrast in this one area by allowing a greater range of values here. Be careful not to repeat this range of values anywhere else on the figure or object.


© John Ennis 2011

Next Topic: Basic planes

Highlight

Look for the highlight on a sphere, like the ball of the nose, on corners, like the edge of the nose, and in corners like where the side of the nose meets the cheek . On the crest of a rounded form inside the center light. On the skin where the surface changes to wet (sweat) or oily. Usually a full value lighter than the form on which it sits.

Paint the highlight in as a teardrop that flows with the action. Shaped like a comet.

It can have soft edges on skin, or hard edges on metal. 

Shifts toward the hue of the light source. The highlight is a reflection of the light source (the skin is not a perfect reflector).

It is an interest-getter.


© John Ennis 2011

Next Topic: The Effect

Center Light

The center light is the main modeling factor out in the light. It takes the flatness out of the  planes in the light area. It makes form out in the light.

It is found only on round forms. 

It is a half value lighter than the average light value.

There are no hard edges on the center light. 

The center light is found and used most effectively on the upright plane. 

It widens and narrows with the form.
Create the center light on big forms first, then break in into smaller forms.

If the average in the light is 7th value, you can  lay in the center light a full value lighter and brush it down on all sides to soften and darken it to 7 1/2. Remember the highlight will be a full value lighter than the average, the center light has to be in between. There is no hue change, hold the local. There is no significant chroma change. It might be slightly weaker, but making it too neutral will weaken the edge plane (edge planes is a subject for an upcoming blog segment).

Once the curved form becomes a corner, the modeling factor
becomes a highlight, not a center light. 

Shape of the form dictates shape of the center light.

As the thumb turns towards body,
the forearm twists and the center light follows. 

In the illustration below, Reilly indicates a step-by-step procedure for painting the center light. After laying-in the light, shadow and halftone, add the center light, softening the edges as needed. Then add the cast shadow from the jaw. 

Try this exercise at home. 

© John Ennis 2011

Next Topic: Highlight