Color Vision 6: The Eye and the Camera

Your eye and your camera "see" differently. The eye roams around and focuses on many points within its field of view—it is constantly active and any peripheral vision limitations are compensated for by a simple turn of the neck. The camera only “sees” in rectangular frames, and focus is fixed on one plane, modified by the depth of field you set via aperture choices. Its peripheral vision is determined by the focal length you choose when using the zoom, or with primes (fixed focal length lenses), by the focal length of that lens.

The top photo was made with "default" or factory settings of the camera. While fairly true to the cast of light on that day, it lacks the "punch" of rich colors created by choosing a "saturated" picture control. Knowing how you want to interpret a scene points you in the direction of making certain settings that will communicate the emotional qualities of the scene you want to express and bring the image more into line with how your mind interprets it.

The colors you record depend upon the prevailing cast of the light under which you photograph, and how you set the color balance accordingly. The eye adapts and constantly balances color, regardless of the source of illumination. For example, a white shirt will be seen as white regardless of the color cast (unless it is very strong), even under artificial light. If you do not adjust color balance (known as white balance) in your camera under, say, incandescent light, it will record as much warmer than the eye sees.

The eye dilates and constricts to adjust for changes in brightness, and while color reception is lessened in low light, that adjustment is automatic. When photographing, we must adjust the ISO according to the light level. That’s because at the moment of exposure the aperture and shutter speed settings record  the energy of the light in one fixed pulse.

In short, the eye/mind is both receptor and active participant in perception, while the sensor in a digital cameras reacts to and records light according to set rules of exposure and sensitivity.

The difference between these two exposures is in white balance settings. The top image was made using "daylight" white balance and one below is made on "tungsten" white balance. Recognizing color casts and changing them to match what the eye sees (top) and what the camera records is an important aspect of aligning what the eye and the camera sees.

The above may seem obvious, but one of the factors in making images with a camera is that we cannot presume that the sensor will respond to what we see in the viewfinder, regardless of the circumstances or lighting conditions. Understanding how the two differ in their response to light, and how we can modify camera functions to make them more in tune with what the mind perceives (and interprets) is one of the most important, and perhaps least understood and appreciated aspects of photography.

The eye (and by that I mean the mind and eye combination) is an amazing instrument that continually sends messages to the brain, where they are woven with other impulses to form images, the codes that form our perception of the world. By comparison, the camera is a light sponge that captures and holds different brightness values and colors. In short, the camera is a machine. We ascribe value and connotation to those brightness values later, when we view the image as a representation of something we previously saw. Again, the eye is active, the camera is passive and requires our active and creative intercession to blend perception and interpretation within our image.

Next posting: The mechanics of image recording.

Color Vision 5

Color Exercises

Let's take a brief break from the tips and techniques of the Color Vision series to do some color exercises you might like to try as a way to exercise your visual muscle. My suggestion is to first look for scenes or past images that fulfill these exercises, and of course use them to compose when you photograph now to see how they work.

 This hand tinted fall scene, adding pastels to embolden the print, was made along the Chama River in New Mexico and shows how color offsets, here the warm colors of the foliage set against the distant mountain and sky, create a feeling of distance and space within the frame.

*Look for complementary colors to offset dominant colors (those that take up most of the scene) or subjects with those colors.

*When shooting in color cast conditions (sunrise/sunset, fog, snow etc) look for offset and accent colors, such as warmer colors with an overcast sky or cooler colors when the sky turns warmer late in the afternoon.

*When working in color "families", look for complementary colors as accents.

While this scene would be characterized as "cool" in overall color cast, the red accent on the life preserver holder on the pole is a complementary color accent that catches the eye. 

*Create a color “shimmer” with equally valued complementary colors.

*Use exposure techniques to change color intensity--overexpose for paler colors; underexpose slightly for increased saturation. When shooting monochrome color scenes, vary exposure plus and minus by1 stop to explore color contrast effects.

*In a distant landscape, cool colors say "distance". Create scale and perspective with complementary colors in the foreground.

*If a foreground subject has a dark color, and the background is dark, seek complementary colors to increase contrast. The same holds true for a light foreground and background.

Photographed right after sundown under an overcast sky, a blue color cast dominates, but is offset by the complementary yellow of the building lights. Note how the lighter hue of blue in the building details offsets against the darker sky.

*A bright color will always dominate a more muted color. Use of complementary relationships will increase the visual energy of the background.

*Explore monochrome effects in different hues.

*In a scene with a family of colors, compose so that one hue dominates the frame, allowing the other hues to play supporting roles. 

Next in the series: How the eye and the camera "see" differently: color recording, color temperature and more.

Color Vision 4

-->

 Color Relationships

Color relationships within a scene create feelings of harmony or discord, of calm or excitement to the eye. Certain color relationships form the basis for color play that has proven fruitful for artists through the centuries.

There are special sets of colors that seem to form a unique bond. Look at the work of painters such as Cezanne, Monet or Seurat, and the photography of Pete Turner or Ernst Haas, and you will discover how color relationships play a special role in both enhancing content and drawing the eye into the scene.

The setting sun striking these bushes on a stream bank  creates an offset against the shaded blue of the rocks and stream behind them, reinforcing and heightening each color and area within the frame. 

One set of relationships are complementary colors, such as red/green, orange/blue, and yellow/violet, opposites on the color wheel. When both colors are present, and in close proximity, they intensify one another. For example, a red or yellow flower will always stand out more against a field of green. The degree of richness and brightness of these opposites also has an effect on the power of the visual response.

The "complementary effect" may explain why we are so dazzled by sunsets. When orange/red clouds intermix with blue we tend to pause to consider the display. Mixed colors in the sky are always more fascinating than a continuous-tone blue.

When colors come from the same general band of the spectrum they are said to be of the same "family". They harmonize with one another, and have an effect on the scene’s mood. We tend to describe these families as "warm" (red, yellow, orange) or "cool" (blue, violet, green.)

The unity and harmony of this bucolic scene is created by the dominance of the warm color cast by the rising sun. 

People have different reactions to certain color relationships. Some tend to find cooler color scheme restful; others find them “cold” and less inviting. Some say that warmer plays are more intense, while others find them peaceful. A "cool" image may be made of a forest floor under a canopy of trees; a "hot" color scheme might be the range of colors in a desert sandstone formation.

Images can benefit from a hint of complementary or even anomalous color thrown in: these "hints" of complements are like strong accents that can attract the eye. Having a dash of "cool" colors in an overall "warm" color scheme can be very effective, and vice versa. Playing with color families and then spicing it with complements can heighten the vividness of any scene.

While the overall effect here is of a "cool" scene (blue dominated), the small branches and red leaf create an accent that catches the eye.

Another fascinating color effect is provided by monochrome (not black and white but color play within the same hue). When we seek monochrome color compositions we are exploring a relatively narrow band of color, with slight variations in saturation and brightness. This differs from black and white photography, where we are dealing with shades of gray, but is analogous to black and white in that texture and tonality can be explored.

This canyon wall is dominated by warm colors within a fairly narrow range of the spectrum, but the lights and darks and streaks of white create a textural visual play. 

The color schemes and plays you choose for your photographs comes down to your taste and subjective reaction to a scene, and there is no right and wrong in what you choose to do. But study of color relationships will open your eyes to more possibilities, and taking chances with color can lead to some exciting results.

Next post: Some color vision exercises

Color Vision 3

The Color Quartet

How we see the color of a subject depends upon the inherent nature of that subject and how it absorbs and transmits the various wavelengths of light that we perceive as red, blue, etc. In essence, things absorb some frequencies of light more than others, then reflect or transmit light as its color. If something looks white (such as brightly lit snow), the wavelengths of all the colors have interfered with one another and canceled, in effect, any color out. If a thing is black, it absorbs all the frequencies and reflects none of them back.  

But the subtlety, the shades and variations of color, are determined by other factors a well. While the subject itself has a “base” color (its selective absorption and transmission of light), the brightness level and direction of the illumination that reveals it, the surface of the subject, be it rough or smooth, and the color cast created by light source itself also have a strong influence on the color we see and record. There is always a dance among the quartet. 

 This bright morning fog provided a strong backlight on the tree, making it appear as a silhouette. Yet, photographed on a sunny day it would show all the color variations within the bark. 

If you look at a tree with a very dark bark backlit by a bright light source, it will look almost black. Look at the same tree with a shaft of light striking it (or illuminate it with flash) and that black may appear brown or even yellow. We more or less take this for granted, and say that the tree is lighter because it's being struck by direct light. Part of that change, however, may result from the effect of the tree's surface, and how it alters the absorption and reflection of the light. Thus, the textural surface can affect how we see the subject brightness and its color.

Late day in northern New Mexico often yields a rich, warm light, the result of the sun's rays slanting low across the western horizon. This ambient light has a strong effect on all the colors within the scene, tinting them in reds and yellows.

The overall quality of the light source can have a profound effect on color. Light and dark tints of color that in flat light would show as one hue become more differentiated in bright light--the effect of color contrast. Yet, if that light is too bright and the surface is glossy we will get greater interference, thus some of the color that we might see in flat light becomes "washed out", overly bright or at least considerable lighter in tone. If the surface is matte, the reflection becomes more diffuse, and we see more color. Thus, the greater the surface reflection, the less the color richness, or saturation we perceive. Rough surfaces throw off all sorts of reflections that can vary the color in many ways, and create a more dimensional effect.

Direct light has a strong influence on how we see color, enhancing contrast and differentiation, especially on rough or highly textural surfaces, such as on the bark of this desert cottonwood in late winter.

 

A strong influence on color perception is the color bias, or nature of the overall light source itself. Atmospheric effects are a case in point, with perhaps the most familiar being so-called “aerial perspective.” If you look at a range of mountains from a distance on a summer’s day, we see them as blue. When we walk or drive closer to them, however, we see them as green, or red, or whatever color they might be. If the ambient (overall) light source has a color cast it may well dominate the way we see color of every subject in the scene.

The same goes for the visible color changes subjects undergo throughout the day. The inherent color, if you will, of sandstone formations do not change, but we all know that photographing those formations late in the day when the slanted rays of sun strike them will yield be the most saturated and vivid effects. The colors may become even more enhanced due to the fact that those rays of light are more amber, which is the color bias of sunlight as it skims across the horizon.

Color proximity has a strong influence on how we see various forms within a scene. This is especially true in autumn when some greens remain among the reds and yellow of neighboring foliage. This color contrast evokes a kind of visual "vibration" to our eyes.

One other factor to consider is the influence of color proximity. The color of any one thing does not exist in a vacuum. It is influenced by the color of subjects around it, and how those subjects absorb and reflect a certain wavelength of light. It's as if we exist in a world of color mirrors, reflectors that bounce from one subject to another. This sets up color relationships, and creates many of vibrations between colors that diminish or strengthen color contrast.

In short, the way we see color is almost subjective--it is certainly conditional. Our perception of color itself is always changing, always being affected by the energy around it.

Next post: Color Relationships

Color Vision 2

Our Perception of Color

Light is colorless. In and of itself, it has no inherent color. As a child you might have noticed this, especially if you got your hands on a prism and held it to catch the rays of the sun and projected it onto a sheet of white paper. Miraculously, that ray of light breaks into bands of color. Rainbows are formed in similar fashion and offer a grander view of this phenomenon, the full menu of ROYGBIV (red, orange, yellow, green, blue, indigo and violet) colors that we can perceive.

This double rainbow resulted from the rays of the setting sun coming from low on the horizon after a storm. The diffraction of the light through water droplets in the sky acts as a kind of prism that reveals the spectrum of color. 

While rainbows inspire awe and wonder, they also offer a catalog of the color frequencies on the electromagnetic spectrum available to humans. That range is  "sandwiched" between ultraviolet and infrared, which are actually available to certain animals and insects, used for hunting and getting around in environments in which we would be blind. (One of the peskier examples are mosquitos, who see us as a glowing target.)

Taken with an IR-modified sensor in a digital camera, this image shows how some creatures "see" into the higher end of the electromagnetic spectrum. In days past photographers had access to IR and "near" IR sensitive film that could do the same, often enhanced via a red filter mounted over the lens.

Stretch that spectrum wider and wider and you enter the world of gamma and radio waves. We cannot, luckily I suppose, see all those waves (consider how driving around with the radio on with both visible sound and light waves coming from the speakers would affect the commute). Auditory nerves take care of sound perception and eyes the visual, both of which are sorted out by the brain. In short, we see color in a fairly narrow band of all the wavelengths around us.

The eye contains receptors that work in concert with certain frequencies, and we see those frequencies as certain colors. What we call "red" is actually a wavelength of about 680 nanometers (one billionth of a meter in frequency, or wave length); yellow light has a frequency of just under 600 nanometers, a narrow gap indeed, but one that indicates the subtlety of color perception. Blue light of the sky has a lower frequency, about 475 nanometers, caused by the scatter of shorter wavelengths by the air itself. If that scatter resulted in a few nanometers difference we might see a red sky above our heads!

(If one needed a rational explanation of how psychics see auras, it might be suggested that they are capable of perceiving color in different ways, or that they can perceive in the fringes of the spectrum that are invisible to the “normal” eye. Attributing physical or spiritual states to certain color emanations is probably more poetic than clinical, and speaks more to our emotional reaction to certain colors and shades than any diagnosis or proposed course of healing.)

Without the "filters" of our visual system we would see the world in interesting, though not very helpful, ways. We can emulate this disorienting visual world with photography using slow shutter speeds and camera motion during long exposures.

Describing color as a neurological reaction to wavelengths is in no way meant to denigrate its wonder, or reduce it to a mere scientific phenomena. Let the idea sit for a while, and begin to look around. This might open you up to seeing and appreciating the amazing energy that constantly surrounds us. Take the time to watch a full sunrise or sunset and notice how the sky shifts in color. Being open to that energy has lots of creative power. It’s a good way to explore ideas about how color can be used as a vital tool for visual expression, and perhaps guide you in choosing the decisive moment to snap the shutter.

Next posting: Color Absorption and Reflection

Color Vision Part 1

Seeing Color

There’s a reason people stand at water’s edge and look into the distance as the sun goes down.

Just after the sun sets, the light coming from just below the horizon reflects off the sky onto the water and back again, filling the world with a dazzling array of texture, color and tone. While those moments seem brief in relation to the rest of the day, they are a profound reminder of the passage of time, and provide a respite between the often hurried day and calm of night. That time of transition is, for some, a quiet contemplation, and a way to once again bathe in the refreshing beauty of pure color and light.

The effect of color on the eye, and the mind, is profound, and can influence both mood and attitude. We adopt color associations from our culture, or create our own through experience or subtle affinities. When we ask: what's your favorite color?, we are seeking clues that others might find by asking: what's your sign? In certain circles and parts of the world, color meditation is used to calm or excite the mind, even to heal the body.

We relate colors to virtually every aspect of our lives, and use them as an important indicator of time and place, of intimacy and space, even of fear and attraction. A calm deep blue sky, for example, is certainly more reassuring than a swirling green one. Deep within our subconscious, the oranges and reds of deep autumn, or the brilliant colors of spring, evoke more than just an understanding that the season is undergoing a change.

Painters study the influence of color on emotions and consciously apply it in their work. Compare the effect of the deep umber and ochre of Rembrandt’s portraits with the vibrant colors of Fauvist cityscapes; of Picasso's blue period with that of Renoir's golden light. Naturalist painters, like those of the Hudson River School, use color and tone as markers of distance and scale, juxtaposing complementary colors of different intensity to create shadow, line and form. Modern abstract painters such as Mark Rothko use "pure" color as vibrational fields that affect us on both a visceral and emotional level. Visit museums to view some of the artist's work mentioned here or, for a lesser though perhaps more accessible view, check out the work online.

While it could be argued that painters have more control over color than photographers, who often rely more on external than internal realities for their picture's content, a thoughtful consideration of the power of color by a photographer is well worth the time. Indeed, any photographer shooting color will do well to understand how color affects subject, scene, point of view, and personal expression and interpretation in their images.

The aim of this series is to explore and appreciate color as photographers, and to use that knowledge first, and perhaps most importantly, to open our eyes to the potential of color in the world around us and apply it to enhance our work. Since we operate through the machine of a camera and lens, that application is both emotional and technical, with each “side” reinforcing the other.

Part 2 of this series of posts will define some terms used and characteristics of color that will give us a common ground as we go forward.

Text and images copyright George Schaub 2018