Nov, 9: Color and Light-Surfaces and Effects Chapter 9

Transmitted Light:
- When Sunlight travels through a thin, semitransparent material, the light becomes richly colored. Light that bounces off the surface is fairly dull by comparison. A, "stained-glass window effect"

Explanation of light passing through the leafs of a cabbage plant:
1. Transmitted light, with intense chroma or saturation in the yellow-green range.
2. The leaf in shadow, facing downward. This is the darkest green, and would be even darker if it wasn't picking up reflected light from the adjacent leaf seen edge-on.
3. The leaf in shadow, facing upward. These ‘up-facing planes’ are blue-green, because they are picking up the blue light from the sky.
4. Sunlight reflecting off the top surface of the leaf. This is the highest tone or value, and the most textural, especially where it transitions to shadow. But the chroma is not very intense, because most of the light bounces off the waxy cuticle of the leaf.

Subsurface Scattering:

- Light enters the skin or any translucent material and spreads out beneath the surface, creating an unmistakable glow. Subsurface Scattering affects forms with depth and volume, such as a person's ear, a glass of milk, or a piece of fruit.

 Three conditions:

1. Translucent Flesh

2. Small forms

3. Backlighting

Tips:

Light traveling beneath the skin turns the spaces between your fingers bright red.

It makes a person's ear turn crimson when they are backlit

Color Zones:

- The complexion of a light skinned face divides into three zones. The forehead is a light golden color. From the forehead to the bottom of the nose is reddish, The zone from the nose to the chin tends to ward a bluish, greenish, or grayish color.

A person who has been physically active often gets a stronger dilation, particularly in the cheeks in a diagonal line running from the inside of the eye to the corner of the jaw. 

The Hair Secret:
- Like water and foliage, hair has always presented a unique challenge to both the traditional and the digital artist. To avoid the stringy look, use big brushes, keep the masses simple, soften the edges, and control the highlights.
- It helps to visualize the masses of hair as a ribbon, the Highlight goes across rather than following the whole length of the strands. 

- Use a large brush
- Keep forms simple
- Try to state the largest masses.


Caustics:
A drinking glass or a water-filled vase can act like a lens to focus light rays into spots or lines of light. the asme effects happen underwater, the result of the undulating waves acting like lenses.

Caustics are the spots, arcs, wavy bands, of light projected onto a surface by means of refraction or reflection from a curved glass or from waves on water. 

- Waves make dancing lines on the sea floor or backs of animals. 

- Underwater caustics can only reach about 20-30 feet below the surface. 

Specular Reflections:

- An object with a shiny surface is like a mirror reflecting an image of whatever is around it. 

- Light Rays bounce off the surface at the same relative angle that they hit it. 

three rules!!!!

1. The more reflective the surface, the larger the value range.

2. Convex surfaces include a smaller reflection as well as objects in the scene outside the bounds of your composition. 

3. Whether traditional or digital, the reflection is a secondary layer added to the modeling already present in the piece.

Highlights:

The location of the highlights on the snake show that it is more flat than cylindrical as it squeezes the crocodile. 

In General, a highlight on any glossy surface is not WHITE but a combination of the source and local color. 

Color Corona:
An extremely bright source, such as a setting sun or streetlight, that is surrounded by a region of colorful light. This appears both in human vision and in photography.

The glow takes on the native color of the source and can be found on refelcted sources such as:

- streetlights

-Car headlights

- solar highlights

-wet surfaces

Motion Blur:

There are two kinds of Blurring:

1. Motion Blur- A Form moves rapidly in front of a stationary observer/camera.

2.Speed Blur- the Camera tracks alongside a fast moving object. 

MotionBlur:

Paint figures and background wet together and then soften edges. 

Slower drying mediums are better. 

Crisp edges take away from the motion. 

To show that the camera is following a middle ground object, then the background should be blurred together. 

Speed Blur:

Only the edges perpendicular to the movement are blurred. 

The lines and objects that are in line with the object in motion should not be blurred. like in the painting above. 

Photos vs. Observation:

Clipping: The Loss of information because of the photosensor's inability to respond to relative extremes of bright or dim light. 

Photos cause:

- Deep shadows to appear pure black

- Highlights appear pure white.

- Colors shift/weaken and become monochromatic. 

- Weak reflected colors are lost.

Saving color with photos when time is short:

- make a color scheme with the medium you are using. 

- Use the photos to document details for reference.

- Make the phots black and white. (Then the colors wont distract you)

- Wait for an overcast day.

- Take a dark and a light exposure.