Image color editing plays a very important role in the post-processing of photographs, because no other aspect can have such a lasting impact on the effect of photographs. After all, color can directly and emotionally affect the viewer of the photo - not only the individual color, but also the combination of multiple colors. When adjusting colors, whether you pursue authenticity or artistic sublimation, harmony or disharmony, softness or brilliance is up to you.
No matter when, every color photo has huge potential for editing. In general, you are likely to develop only a small part of it, and rarely really tap all its potential. Why? If you've done editing with one or more color regulators in photo processing software, you'll understand that everything is possible in the field of color processing. Of course, the treatment you like has to be conditional. If you not only post-process your own photos, but also do the work for others, then you should not leave the color of the images to luck only.
True and false colors
Basically, there are two purposes to adjust the color of the image: one is to obtain credible and natural color, the other is to make the color "strange" creatively.
In order for an image to get a real color impression, you have to ask yourself a question: which colors must be "right" to make the whole image look real? The answer is simple: memory color. Human beings have a deep memory of certain colors, so they know at all times what they should look like - these colors are called memory colors. For memory colors, even very small color skewness people can feel, and think that this color is unnatural.
Memory color is not necessarily a well-defined color. It usually refers to what color an object is not: rose is not grey, sweet paste is not pink, lemon is not purple, grass is not red, giraffe is not green - here are just a few examples. In addition to the above, even color changes are firmly preserved in our memory, so that we all know what color the sky will be dyed, or what color the green plants will appear in the shadows, even though none of these things has a clearly defined color. In addition, in any case, the most important color of memory is always the color of human skin. Although there are many differences in skin color, once they deviate from the color pattern stored in our memory, they will make us feel very uncomfortable.
Of course, there will also be such a situation, some kind of artistic approach makes the color in the image deviate from the memory color, and this result is still convincing. But this kind of situation is rare, more often, false memory color will give people a color distortion, unbelievable impression, this impression makes people feel that these colors need to be further adjusted.
If you find it boring to pursue lifelike color effects all the time, we can assure you that even with emphasis on memory color, the creative space for color adjustment will not be too limited.
Color Attribute (HSV Color Attribute Mode) HSV
Color attribute mode is the basis of digital editing of color, that is, the use of various color adjustment tools. It combines the three basic attributes of each color - Hue, Saturation, and Value, or Lightness, Brightness, Intensity, which are abbreviated as HSL, HSB and HSI.
Among them, the color contrast reflects the visible light of different wavelengths reflected by the object. Each color has its own position on the standard color wheel, corresponding to red, orange, yellow, green, cyan, blue, purple or magenta, or their mixed colors. There are 360 hues in HSV mode, each of which is expressed by a degree.
Saturation refers to the purity of color and the brightness associated with it. The more saturated a color is, the smaller its gray scale will be and the brighter it will be. The more unsaturated a color is, the larger its gray scale and the smaller its color scale. In extreme cases, it is in a non-color gray state. In HSV mode, the saturation level ranges from 0% to 100%: 0% corresponds to 100% gray scale, showing no color gray image, and 100% corresponds to no gray, completely saturated pure color.
Brightness refers to the proportion of light in a color: the larger the proportion of light, the brighter the color, and the smaller the proportion of light, the darker the color. As for how the color changes with the proportion of light, we can get an intuitive understanding of the color impression of an object which is partly in the sunshine and partly in the shadow. In HSV mode, the brightness ranges from 0% to 100%. Among them, 0% corresponds to neutral pure black, without any proportion of colors, and 100% corresponds to pure white, which is also neutral. Therefore, at its 101 brightness levels, the brightness of color corresponds to only 99 levels.
In addition to 101 brightness levels, the HSV model contains 3564000 different colors. Whatever the specific purpose of your photo processing, and whatever tools you choose, you can use these colors to adjust the color of the image.
Any photo processing software will provide at least one tool for manual color modification - usually with multiple such tools. In theory, you have two different approaches. One way is to move the color regulator along the spectrum of visible light. That is to say, you can move the regulator around the color wheel clockwise or counterclockwise, so that the color can be changed from red to orange, yellow, green, cyan, blue, purple or magenta. When moving, one can input a specific wavelength value or degree according to one's own feeling or pertinence.
The advantage of these tools is that they really only affect the color phase in the image, while the distance and relationship between different colors remain unchanged. For example, if red turns orange, the latter turns yellow, yellow turns green, and so on. In addition, the distribution of brightness remains unchanged. For this reason, this wheel-oriented approach is very suitable for adjusting color deviation, such as the color deviation caused by modifying the white balance. Photoshop: Image Adjustment Hue / Saturation Hue | Photoshop Elements: Enhancement Adjustment of Color Adjustment of Hue / Saturation Hue PaintShop Pro: Adjustment Chromaticity / Saturation / Luminance Chromaticity Gimp: Color Hue / Saturation Hue Adjustment Aperture: Adjustment Color Hue | Lightroom: Modify Photo HSL Colour Modify Photo Colour Colour Camera Raw: HSL / Gray Level Colour | Nik Software: Color Efex Pro Colour Contrast Colour
The second method is to move the color regulator between the color poles (in the relative position of the color wheel), that is, between complementary color pairs. Blue and red, magenta and green, as well as yellow and blue can form such color poles. If a color is changed in the direction of yellow, then blue will inevitably become less. In this way, although the color in the image is still balanced in brightness, the brightness distribution of the image is affected. This is because each color has its own unique brightness, which is only related to its wavelength.
When the wavelength is 550 to 600 nanometers, all the color receivers in the eyes respond equally, so people will feel the color is very bright. For example, yellow is much brighter than purple (purple has the lowest brightness). If the yellow in the picture is replaced by blue, the picture will be darkened. To counteract this effect, the brightness of the whole image can be maintained unchanged. But not every photo processing software can do this, and there is also a drawback, that is, in order to ensure brightness, in addition to blue and yellow, other colors will be adjusted. As a result, this leads to some unintentional (and uncontrollable) color changes. Photoshop: Image Adjustment Color Balance | Image Adjustment Optional Colors | Photoshop Elements: Enhancement Adjustment Color Change | PaintShop Pro Adjustment Chromaticity Mapping Gimp: Color Color Balance
Modifying White Balance
In the process of color processing, a special case is to adjust the white balance, which is done when converting RAW files. Processing tools for this purpose provide a variety of pre-defined light scenarios (such as shadows, incandescent lights) for selection, or the possibility of manual adjustment. The latter can be done either by using a straw to define white dots directly in the image, or by using two different regulators: one moves between blue and yellow poles to obtain different color temperatures, and the other moves between magenta and green to change the color phase. The combination of the two methods can correct the color deviation caused by the white balance error in the image. PaintShop Pro: Adjustment Color Balance | | Gimp: Color Automation White Balance | Aperture: Adjustment White Balance | Adjustment Effect White Balance | Lightroom: Modifying Photos Basic White Balance | Camera Raw: Basic Effect White Balance | Nik Software: Color Efex Pro Cross Balance Color Ex Pro _Pure white neutralization
Modify color saturation
As with color modification, each photo processing software can adjust the color saturation. These adjustments follow the same principle: increase or decrease the gray level of a certain color by 50% - depending on whether the saturation should be increased or decreased. At this time, the scale value ranges from - 100 to + 100, where 0 corresponds to 100% saturation. Negative values represent the reduction of saturation in the direction of gray level, while positive values can make the image color more saturated. If used properly, such "more saturated" will have a good effect, but too high a value will cause ugly, obvious color spillover phenomenon. Photoshop: Image Adjustment Color/Saturation Saturation Image Adjustment Change Saturation Photoshop Elements: Enhancement Adjustment of Color Adjustment of Color/Saturation Enhancement Adjustment of Color Change of Color Saturation Paintp Pro: Adjustment Chromaticity and Saturation Chromaticity/Saturation Degree/luminosity saturation | Gimp: color hue / saturation saturation Aperture: adjustment color saturation Lightroom: modification of photos HSL saturation modification of photos color saturation modification of photos basic preference saturation Camera gray saturation basic saturation saturation saturation Sum | | Nik Software: Color Efex Pro Tone Contrast Saturation Color Efex Pro Name of Contrast Filter Saturation
To solve this problem, a more flexible saturation adjustment method has been developed: when a certain color approaches 100% saturation, the treatment intensity will be weakened. In this way, the brightness of the unsaturated image area can be increased, and the saturated image area can not be changed too much. Photoshop: Image Adjustment Natural Saturation Natural Saturation | Lightroom: Modifying Photos Basic Preference Brightness | Camera Raw: Basic Natural Saturation
Modify color brightness
In addition to adjusting hue and saturation, most color adjustment dialogs also provide a third adjustment function to modify the brightness of the color. The way to adjust is: to get a lower brightness, mix in black; to get a higher brightness, mix in white. Photoshop: Image Adjustment Chromaticity / Saturation Lightness | | Photoshop Elements: Enhancement Adjustment of Color Adjustment of Chromaticity / Saturation Lightness PaintShopPro: Adjustment Chromaticity / Saturation / Luminance Luminance Gimp: Color Hue / Saturation Luminance Adjustment Aperture Color Adjustment Saturation | Adjustment Color Brightness | Lightroom: Modify Photos HSL Brightness Modify Photos Color Brightness | Camera Raw: HSL / Gray Level Brightness
The continuity of brightness changes along the gray scale. Therefore, brightness adjustment can not only use color adjustment tools, but also use tools to adjust tone and contrast. In addition, the curve dialog even allows for much more precise adjustments than the general brightness regulator, because with the help of the curve tool, we can modify the brightness of a certain tone value area individually. Photoshop: image adjustment brightness / contrast brightness image adjustment color level image adjustment curve Photoshop Elements: enhancement adjustment of light brightness / contrast brightness enhancement adjustment of light color level PaintShop Pro: adjustment brightness and contrast brightness adjustment Integral Brightness and Contrast Histogram Adjustment Adjustment Brightness and Contrast Curve Gimp: Color Brightness Brightness Color Curve Aperture: Adjustment Exposure Brightness Curve Adjustment Color Lightroom Modification Basic Hue Exposure | Modify Photo Tone Curve | Camera Raw: Basic Brightness Tone Curve Parameters / Points Nik Software: Color Efex Pro Color Contrast Brightness Color Efex Pro Name of Contrast Filter Brightness
Choose Editorial Scope
The color adjustment methods mentioned above all act on all the colors appearing in the image, but it is only rarely necessary to make such a holistic modification - basically, only when the holistic color bias is eliminated or a holistic color bias is intentionally added from a creative point of view.
More often, only some of the colors in the image need to be adjusted separately. Because only in this way, the color effect can be enhanced or optimized, and the resulting image will not appear color distortion or obvious as processed. Therefore, it is very important to understand the functions of separated editing areas and various methods of independently editing single color.
Of course, here, as with any other processing, manual selection and the use of layers and masks are considered, but both approaches are complex. Another option is to use generic color or brightness processing tools, which can filter out individual colors in an extremely simple and fast way, but they work in completely different ways.
The first kind of tools, they can either select a kind of color (such as "red tone", "blue tone") or provide several regulators, each type of color can be operated independently. In general, the color "categories" here are well defined, and they are not divided by the distance on the chromatogram, but by the degree of subjective discrimination. In addition, some editing tools also support manual determination of the color to be separated: if you are not sure which range of color you want to edit should belong to, color selection tools (such as pipettes) can help you mark it on the color ring or palette. Photoshop: Image Adjustment Hue / Saturation Image Adjustment Optional Color Photoshop Elements: Enhancement Adjustment of Color Adjustment of Color / Saturation PaintShop Pro: Adjustment Chromaticity Mapping Gimp: Color Tone / Saturation Aperture Adjustment Color Lightroom: Modify Photos HSL Modify Photos Color Camera Raw: HSL / Gray Level
The second kind of tool can adjust the specific tone value area separately. These areas are "shadow", "middle tone" and "highlight", which correspond to the darker, brighter and brighter areas in the image. The transition of these areas in the image is very smooth. After some practice, you will find the feeling that you can see at a glance which image areas belong to which tone value areas. Photoshop: Image Adjustment Color Balance | Photoshop Elements: Enhancement Adjustment of Color Color Change | Gimp: Color Color Balance
The third kind of tool makes good use of the fact that all colors in an image are composed of primary colors, which vary according to the color space chosen. Generally, these primary colors are red, green and blue, which correspond to three color channels, each of which can be edited separately. However, the prerequisite for selective color adjustment through color channels is that you know the composition of the mixed color. For example, if you want to edit the yellow in the image, you need to adjust the red channel to the same extent as the green channel, while orange needs more influence from the red channel (relative). For the green channel, the blue channel remains unchanged. It's helpful to see the effect map of color mixing. Photoshop: Image Adjustment Curve Image Adjustment Color Level Photoshop Elements: Enhancement Adjustment of Illumination Color Level PaintShop Pro: Adjustment Color Red / Green / Blue Adjustment Brightness / Contrast Brightness Adjustment Brightness and Contrast Column Adjustment Gimp: Pigment COLOR CURVE | COLOR COLOR GRADE | Aperture: ADJUSTMENT CURVE | ADJUSTMENT COLOR GRADE
The fourth kind of tools work on the basis of separating one color and replacing it with other colors when necessary. Through targeted editing, the brighter shade of the wall is further strengthened. Likewise, the sky reflected in the windows was strengthened by adding blue and a little blue separately. 06 color 165 automatically adjusts the color by checking the white balance to confirm whether there is color bias in the image. The brightest part of the image is defined as pure white, and the other colors are scaled to match it. Similar to automatic white balance, the results of this process can show natural colors, but sometimes there will still be color bias. Change. Usually, the choice of colour is made through a straw or similar tool. You can create a selection or mask by clicking on the desired image area. Sometimes you have to manually modify the selected area or mask created so that you can control the final color area to be edited. Photoshop: Image Adjustment Color Replacement Selection Color Range Tool Magic Wand Tool Tool Quick Selection Tool Photoshop Elements: Enhancement Adjustment Replacement of Color Tool Smart Brush Tool Tool Tool Quick Selection Tool Gimp: Color Mapping Color Exchange | Toolbox Color Selection Tool Toolbox Foreground Selection Tool Toolbox Fuzzy Selection Tool Aperture: Adjustment Fast Brush Lightroom: Modifying Photos Tool Adjusting Brushes Camera Raw: Adjusting Brushes Nik Software: Control Points (U-shaped Points)
Automatic color adjustment
Of course, in addition, any photo processing software has a variety of tools to automatically edit the image color according to clearly set parameters, and it is very fast and efficient. Some processing software and some "small experts" specializing in certain aspects of color adjustment, such as removing red eyes, modifying skin tones, targeted removal of a certain color bias, and so on. These tools can sometimes produce amazing results, but just like the camera's automation when taking pictures: if you hand something over to software, you lose all control over the results; even if you like the resulting image effects, you don't know how it came about. Therefore, it is worthwhile to strive to understand each processing tool and really learn to use them effectively. Not to mention how much fun you can feel when you process a picture that works well and persuasively, it's attractive that you can optimize your process on this basis and repeat it at any time. Photoshop: Image Autotone | Photoshop Elements: Enhancement Auto Color Correction Enhancement Adjustment of Color Removal of Color Bias Enhancement Adjustment of Color Adjustment of Skin Color Enhancement Auto Repair of Red Eyes PaintShop Pro: Adjustment Color Fading Correction Adjustment Intelligent Photo Repair Automation Color Enhancement | Aperture: Adjustment Effect Color | Lightroom: Modifying Photos Tools Red Eye Correction | Camera Raw: Red Eye Removal
Identifying color deviation
Whatever tool you choose to adjust the color of the image, you must first identify which colors are not real, that is, where the color bias occurs. Recognition of color deviation - In addition to an accurately calibrated display, you also need a pair of sophisticated eyes or analytical tools that can provide you with the corresponding data values. The key here is "gray balance".
Because when the brightness value of each color channel is unbalanced, the color deviation will occur in the image. This does not necessarily make the whole image produce a very obvious color bias, it may also involve only one tone value area. To determine whether there is a color bias and which color channels there are, you need to measure the value of a point in the image that should have been medium gray, white or black. To find such a point, you need to practice more, because it is greatly influenced by the subject of the shooting. It is not always easy to find, but it is not irregular. For example, in a portrait photo, people's pupils are black; in a landscape photo, you may find a white cloud in the sky; in a city photo, the walls of streets or buildings are mostly gray.
If you have found the desired point in the image, you can use the straw to measure its brightness value. The color channel that deviates from the balance must be corrected so that the image can get a balanced color. For example, if the checkpoint is 153 in the red channel, 157 in the green channel and 110 in the blue channel, the result is not immediately clear, especially when taking a souvenir photograph - there is too little blue in the image. If there is too little blue, the image will be markedly yellow, especially when these values are quite different, which you can see with the naked eye.
If you have identified the color bias, you can reduce the corresponding color in the image or add its complementary color. These complementary color pairs are red and cyan, green and magenta, blue and yellow.
If you prefer to deal with numerical values, you can use curves or other color channel-based tools to directly balance numerical values in each color channel. At the same time, it is always good to check with the naked eye, so that the eyes can be trained in recognizing color deviation.
Creative Color Composition
In general, color bias does have a negative impact on image persistence and should be removed. The methods mentioned above can be used not only to adjust color bias, but also to create creative color composition. In order to use these functions pertinently, we should first familiarize ourselves with the basic color effects.
Red, orange, yellow and red-purple give the image a warm and comfortable feeling, and appear intimate, soft and friendly, which can remind people of the yellowish prints in film photography.
Blue, cyan, green and blue-purple are cool, alienated and cold, but they give the image a neat, clean and almost hospital-like effect.
Highly saturated colours are very striking, direct, noisy and visibly entering the foreground. They draw attention to themselves and may be the determinant of the subject matter of the image.
Unsaturated colors are more subtle in expressing their emotional effects. They are not publicized. They set off other elements. As a result, the images look elegant and artistic, but they may also be dull and dirty.
Brightening colours have no luster. They lose their saturation, but retain a clean and friendly effect.
Darker colors appear more saturated at first, but as brightness decreases, they become dull and insignificant.
Context-appropriate color editing
The emotions expressed by a photograph are largely conveyed by the color atmosphere of the image, so you can adjust the color according to the image language (or the emotion to be expressed). We know that each type of photographic subject has its typical image color. These colors are summarized through specific photographs, of course, but there is no 100% clear demarcation between them.
Landscape photography. Documentary photographs of plants and animals reflect the charm of nature, so it is not appropriate to use strange colors here to create a strong cosmetic effect.
The alienation effect of color can also interfere with portrait photographs depicting characters. This kind of portrait photography wants to capture the personality characteristics of the person being photographed, so it cannot tolerate elements that divert attention.
Still life, products, flowers and other artistic-oriented themes provide a lot of color editing space, but in any case, the theme's identifiability should be placed in a more important position than artistry.
In general, photographs showing lifestyles and images should first give viewers a positive impression, so they are suitable for clear, bright and saturated colors.
Research, documentary and news photography require authenticity, but color must also be able to strongly express image emotions or more eye-catching. According to the topic requirements, if the atmosphere should be serious or melancholy, you need to use dark, dull and unsaturated colors.
Beauty and fashion photographs mainly work on the emotional level of the image. Generally, they require a thoughtful and detailed color scheme.
To achieve a gloomy, heavy and mysterious Gothic aesthetic effect, a darker, saturated blue-green tone can be used.
Contrary to the above, fairy-tale, fairyland-like, gentle photo themes are created by unsaturated, brighter colors and a larger proportion of white, yellow and orange.