Photography must explain color theory in detail
In this article, we will systematically explain color photography for you. Maybe many photographers will ask what is the topic of color photography? Indeed, color photography has already become the mainstream. Our world is full of color. Everyone is taking color photos every day. It may not be difficult. However, if you want to take wonderful color photos, you should start from the most basic knowledge of color photography, see what color is, how to make good use of color, and the relationship between color and perception, so as to make your color works better. Especially for novices, understanding the theory of color can save you too much wrong costs.
Color photography has been neglected
If we say that color photography has been ignored, we may think it is too much. However, many photographers who grew up in the digital era take color photos when they pick up a digital camera. What they see in their eyes is also the color world. How natural everything comes. However, seeing and taking pictures may not be good. Experienced landscape photographers will not lift the camera at will when they see the picturesque scenery, because they feel that the color is not perfect. Even if it is blue sky and white clouds, they may feel that the saturation is not enough and the contrast is not obvious. For beginners, it is too easy to satisfy and press the shutter.
The middle difference is the understanding of color. If you don’t know what is color contrast, what is color feeling, and how to highlight color, it is often to take what you see, then you don’t know how to choose a more appropriate time and opportunity to find a better angle to take better color photos.
Digital photography is black and white
Is digital photography originally black and white? It’s true that CMOS or CCD can’t distinguish color, they can only read the data of light intensity, so smart scientists have installed RGB filters on CMSO and CCD to let each pixel read only the intensity of R, G and B colors, and then mix the ever-changing colors in the image processing chip.If you check the data, the earliest digital camera can only shoot black and white. At that time, it was the age of color film. But because CCD and CMOS have not been equipped with RGB filters, they can only shoot black and white. Then color digital photography appeared.
Brief History of Color Photography
Our world is full of color, but the only photography that can “truly” record our world began with black and white. When photography was published in 1839, it can only record the light and shadow. In other words, early photography can only take black and white images, but human beings are not satisfied with this kind of monochrome image. As early as the early 1840s, people began to study how to record color images, In the following 100 years, many scientists and photographers have conducted different studies on the technology of recording and reproducing color images. The appearance and preservation of early color images are not ideal, but there have been improvements during the period, so that the perfect color photography was finally realized at the beginning of the 20th century.
James Clerk Maxwell, a Scottish scientist, first proposed the theory of three colors in 1855. Thomas Sutton, a British photographer, quoted this set of theories to create the first color picture of human beings in 1861. However, the color image technology at that time was far from being able to truly reproduce the true color.
By the 1930s, Kodak in the United States and Agfa in Germany launched more convenient Kodachrome and Agfacolor color film respectively, which officially made photography enter the modern color photography world. By the 1980s, when people bought films from photography shops, no one would ask whether they wanted black and white or color, because photography had fully entered the color era at that time, and black and white photography has since become a thing for photographic artists. Even the fast news photography has entered the color era in the mid-1980s. It can be said that photography has entered the digital era, that is, the era of color digital images. Only a few photographers still insist on shooting with black and white film, or converting color digital images into black and white images for display.Although today, digital photography is a thorough world of color photography. You can get excellent color images by picking up any digital camera and pressing the shutter. Because color is an extremely complex image element, it is very useful to learn more about color in photography if you can use color to express art or information.
James Clerk Maxwell, a Scottish scientist, first proposed the theory of three colors.
The above picture is not actually color photography, but painted on black and white photos. Felice Beato (1834~1907) took photos in Japan from 1863 to 1877.
Thomas Sutton, a British photographer, quoted the theory of three colors to create the first color picture of mankind.
The picture above shows Thomas Sutton, a lecturer and photographer at King’s College, University of London, making color negative films for his experiments in 1861.
The Lumiere brothers of France successfully invented the first commercially viable glass color image technology Autochrome.
George Bernard Shaw is a person who loves photography. The picture above shows Bernard Shaw taking a picture of Coburn.
Kodak in the United States and Agfa in Germany respectively launched more convenient Kodachrome and Agfacolor color film.
In 1938, Williams took a picture of Fistaville pottery, and color film had begun to appear at that time.
Photography has fully entered the color era, and black and white photography has since become a thing for photographic artists.
When the new century comes, digital photography begins to replace film photography. It is inevitable to take color images. On the contrary, black and white images are usually bleached by color photos.
Color is only electromagnetic wave
Strictly speaking, the object itself does not have a fixed physical color. When we see the color on the object, we actually see the light waves of different wavelengths reflected on the surface of the object. Therefore, the color of the object will change due to the colored light of illumination. For example, we see green leaves only because they can reflect green light, and absorb other colored light in the spectrum; The snow in severe winter will reflect most of the colored light in the spectrum, so we can see the white snow. On the contrary, the black object absorbs most of the light and color, so we can’t see the color. Besides, because the black object attracts a lot of light, the black object in the sun is hotter than the white object.Because the color of an object is determined by its reflection and the light it radiates, if the spectrum of the light source changes, its color will also change. For example, the “white paper” we see in the midday sun is “normal” white, but when we look at the same page of “white paper” at dusk, because the wavelength in the spectrum is longer, the red in the tone is heavier, and the “white paper” will turn orange.
The reason why we see the color on the scene is that the surface of the scene reflects light waves of different wavelengths.
Range of visible light
The light we see mainly comes from the sun, that is, the sunlight in natural light. With the change of time and weather, we can see different colored light; The reason is that the spectrum of white sunlight is actually composed of a series of colored light of different light waves. When they are refracted and reflected through the atmosphere, they will appear different color deviation. In fact, the rainbow appearing in the sky after the rain is the refraction of nature’s light. From it, we can see the continuous changes of seven main colors in the spectrum, namely, red, orange, yellow, green, green, blue and purple. We can use three mirrors to refract the light into a rainbow color band, and different color lights stand in front of us.
The seven kinds of color light are actually a range of light waves, that is, the range of color light that can be seen by the human eye, about 380 to 780 nanometers (nm). The red wavelength is the longest, about 780 to 620 nanometers, while the shortest visible to the human eye is purple, about 430 to 380 nanometers. Beyond these two limits are infrared and ultraviolet light. Although the range of color and light we see is the range between the two, for photography, especially in the digital era, we cannot ignore the possibility and image of infrared and ultraviolet light in photography creation.
Color exists because of light
Color is actually a very abstract thing. It can be said that it is a kind of “visual perception” of human beings. It can neither touch nor have a fixed form. In physics, it is a band in the spectrum. Without light, there is no color. When we see color, we must attach to a form illuminated by light. Because color and light have an inseparable relationship, we can’t see anything in the case of total darkness, You can’t see any color. But does this mean that we can’t see the “color in the dark” just because there is no light, and the color itself still exists in the dark? The answer is no, because there is no light, color does not exist. Color exists because of light. Different colors are formed by different light waves, so there is no color without light.
There is no color without light, and light and color are inseparable.
Influence of light source on color
When the light shines on the surface of an object, it will absorb part of the light wave and reflect the rest, so we can see the “color of the object”, but in fact, what we see is the light wave reflected by the object. Because of the reflective properties of materials, only specific light waves can be reflected, such as red apples, which can only reflect red light. Therefore, we can see red apples under normal lighting. If the red light waves are missing from the light source, it means that we can only see a black apple. Photographers with traditional darkroom experience know that green objects will turn black under the illumination of red safety lights. This is because the green object can only reflect green light, while the red safety lights in the darkroom lack green light waves, so the object cannot reflect light, so it becomes black.Therefore, whether an object can reflect a certain kind of color light, or what kind of color light it reflects, also depends on whether the light source contains the spectrum of this range. Therefore, the color of an object depends on the physical phenomena of both the light source and the object.
Whether an object can reflect a certain kind of color light or what kind of color light it reflects depends on whether the light source contains the spectrum of that range.
What is color constant perception?
For example, at noon on a sunny day, all colors seem to be normal, but at about two or three o’clock in the afternoon, the colors of everything seem to have little difference, but in fact, the color light has changed slightly.
The white paper seen in the midday sun is probably standard white, but by about 3:00 p.m. and 4:00 p.m., because the color temperature has decreased, the sun is actually yellow, and the white paper should be slightly yellow, but ordinary people may not notice this change when they see it. Why? This is because the human brain will mix the color signals generated by the retina with the signals recognized by the brain on white paper, so we still treat the yellow white paper as white paper, or greatly reduce the feeling of color deviation, which is called “Retinex”. Because the color of an object (the color we can see) is determined by the light wave projecting light and its response to light (absorption, reflection or illumination), But we have a predetermined color of inward reflection for familiar objects. As long as the color difference is not too far, our brains will also accept it and be “deceived” by it.We can do a simple experiment. On a cloudy day, the sun shines on the earth through thick clouds, and the color temperature is slightly higher, and a little bit bluish. If we read indoors with a light bulb for a while, and look out of the window, we will see a very bluish scene. The reason is that we are accustomed to the warm color temperature, and understand the yellow ones as light colors, or even white, which are not so yellow. Once we change to a higher color temperature, You can see the bluer picture. As long as you keep looking at the environment outside the window for a while, the bluer picture will be improved again.
Be deceived by perception when shooting
This subjective cognitive bias of color in our vision often leads to the photographer seeing the wrong color before shooting, or not being able to detect the existing color deviation, resulting in serious color deviation in the captured image. For example, when using a digital camera to take a portrait in a leafy forest, there is a large area of green around, reflecting a large amount of green light, which is mixed with sunlight on the face, and the face is actually green, However, this kind of color bias is not easy to be seen by people on the scene, because “constant color perception” makes our minds moderately adjusted, which actually creates an “illusion” of color. If you watch the image taken by the digital camera immediately, you can see the color deviation of the human skin. Neither previous films nor today’s digital cameras have this “constant color perception”. They have absolute insight into color and are meticulous. They can record the “absolute” color and get the color tendency that can not be seen by the human eye on the spot. Therefore, to learn color photography, you must first learn to “see color”, and distinguish the color deviation procedure under different lighting conditions by experience, and don’t be fooled by inertia, In order to avoid taking pictures with partial color.
In the real environment, sunlight at different times causes color changes, but we may not be aware of it at all.
The example of looking at green objects under a red light mentioned above is an extreme case. If only a part of the spectrum is strengthened or weakened, and the color light has a slight change, then the light that shines on the object itself has a “color bias”, and the reflected color also has a difference. The color will actually change, but usually the human eye is not easy to detect these subtle slight color bias, The reason is that the brain has a fixed perception of the color of objects, that is, it has a color illusion of familiar objects or environments.
There are some basic theories about color in the above. Let’s continue to talk about a series of scientific discrimination methods about color to understand color fundamentally!
Color point classification
In our general concept, the color is not only red, orange, yellow, green, blue, blue, purple, but also the change between them. The thicker, lighter, or darker ones are the possible changes of color. In addition, the mixing of different colors makes the color can have unlimited changes; In addition, the common people’s concept of color includes “black”, “white” and different shades of “gray”. However, in the concept of photography, black, white and gray are neutral colors. In the color theory, black and white and gray are “colorless”.To master the role of color in photography, we must first learn to distinguish color. Color can be distinguished by three attributes, namely hue, saturation and lightness, which can bring different changes to color.
Through the color wheel, we can simply understand that color is changed by Hue, Saturation and Lightness.
What we are familiar with is that red, orange, yellow and other colors with longer light waves belong to “warm” colors, giving people the feeling of warmth, enthusiasm and activity.
But we should also know.
Hue refers to the basic color, that is, the cyclic changes between red, magenta, blue, cyan, green and yellow. The changes between them are continuous and gradual, which can be represented by Hue Wheel.In the hue ring, the relationship between the two colors directly opposite each other is the complementary color. For example, the cyan opposite the red is the complementary color. There is the strongest contrast between them. When the contrast color is used on the photographic picture, the strongest color contrast will appear; On the contrary, the adjacent colors in the color ring belong to similar colors. If similar or connected colors are used in the photographic picture, the picture will appear harmonious.
Basically, a single color itself can change from its own intensity to different shades of color of the same tone. Any color can gradually fade from the thickest saturated color to “colorless”, changing into different shades of gray. When the color is the most intense, that is, the highest chromaticity is the most bright color. Normal images should not have this kind of thickest color. Once the color exceeds the normal saturation, it is oversaturated, making the image look extremely unnatural.
In addition to “hue” and “saturation”, color brightness changes can also make colors look different. Brightness refers to the brightness of color or the intensity of chromatic illumination. When the intensity of chromatic illumination is large, the color will appear quite bright; When the brightness is strengthened, the color can change from normal to bright to overexposed, and then the color will disappear and become white. However, when the color light weakens, the original normal color appears to become dark and dark, and then becomes black when it weakens again. To experiment with this, you can use the exposure compensation of the digital camera to make an exposure of ± 5EV, and the subject of shooting bright color can see the color changes from normal black and white. General merchandise photography habits用的由彩色渐变到黑色的背景，便是利用一种颜色不同的明度变化来造成的渐变色的效果。
进一步说，利用红光(R)及青光(C)两种光混合，也可以产生白光，原因是青光分别是由蓝光及绿光混成，红色光混合青色光，便等于红、蓝、绿三种色光混在一起，所以便成了白色。如此类推，绿加洋红(Magenta)或蓝加黄(Yellow)也一样可以得出白色光。因此，以上的红(R)青(C)、蓝(B)黄(Y)及绿(G)洋红(Y)三对色彩，称作互补色(Complementary Colour)。每一对互补色均有最高的色相对比(Contrast ofHue)，对色彩视觉有最大的刺激，可以营造出十分悦目及活跃的画面气氛，因为摄影师可以因应需要利用高色相反差来制造刺激的画面，反之，若想影像看来略为和谐，则要避免色相的强烈相比。