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In the process of image revision, color difference is a taboo problem for every photographer, especially for beginners, who do not know more in-depth color management methods, resulting in computer-derived images to be viewed differently on mobile phones.

This article gives a comprehensive and detailed explanation of the whole process of color correction and color setting.

Clarify the concept first:

Color correction refers to the use of color calibrator to correct the display.

Color settings refer to software settings in Photoshop

The following points are explained:

1, color correction is not once and for all, monitors have color stability, with the passage of time, color slowly reduce accuracy. It's just that a good display is more stable and can be accurate for a longer time. Better monitors can correct colors once every four months, and low-end monitors with less than 2000 may lose their accuracy within a month.

2, not all monitors meet the color correction requirements, the premise of color correction screen panel color gamut must be more than 95% of the sRGB, because the color correction meter will only correct the color deviation, there is no way to increase the color of the panel. Therefore, it is necessary to cover the color gamut of the panel itself to meet the standard, and if the display parameters are very poor, color correction is useless. The Delta E value of the monitor cannot be changed from △ E < 6 to the professional standard of △ E ≤ 2 by color correction.

3. Many display manufacturers say they have factory school colors, but in fact, some manufacturers do not make factory school colors because the time cost is too high. Basically only a small number of professional display manufacturers can do it, such as BenQ. However, including Apple, the factory color can only achieve about 90% accuracy. I have measured the color space of the new machine, which is generally 88% to 92%, while after color correction, it can reach more than 98%.

First, the color correction method of the monitor takes the red spider color correction instrument as an example to show you how to operate it. Red Spider is also a relatively fast and professional color school instrument in my opinion.

First of all, you need to download a school color driver software on the computer, which can be downloaded on the official website of Starscream. The website is as follows:

Https://www.datacolorchina.cn/zh-hant/photography-design/support/download/

Download the options shown in the following figure

Note: when coloring, you can't choose a dark room or a place where strong light shines directly on the screen. It should be soft natural light.

The color calibrator is connected to the host computer, open the driver software and activate it first.

Select "Software Activation" in the menu bar above

At the bottom of the color calibrator box, the serial number is printed, and the activation can be completed by entering it.

Then the color correction begins, and the following interface appears, with instructions for operation, as follows:

Warm up the monitor first, and then select the calibrated monitor.

Workflow, choose "progressive assistant" is more convenient and intelligent.

If this is the first time to calibrate, select FullCAL.

The color temperature of the monitor is selected as the standard or the 6500K gamma value is selected as 2.2.

What is the gamma value? The relationship between the image input value and the brightness of the display output affects the grayscale and brightness of the image displayed.

Place the color calibrator at the prompt on the interface, make sure it doesn't slide, and then click "start color correction".

This prompt appears during the color correction process, which allows you to adjust the brightness of the monitor to the exact value, the target 120 is the exact value of the target, and the current value is your current brightness.

So adjust the brightness of the monitor until the current value is close to 120, and then click the blue "Update" button.

Wait for the monitor color correction to be completed.

After color correction, you can view the color space data of the monitor, and the bright-based sw270c display can achieve 98% Adobe RGB after color correction.

Apple's 16-inch laptop can reach 99% of the P3 gamut after color correction.

Second, Photoshop color settings in the process of image revision software operation space and color settings are particularly critical, will directly affect the picture color and picture quality, some students will encounter color levels break or export after the picture color difference is big, this tutorial is for you to solve this problem.

The software settings are divided into three parts.

I. ACR setting

II. Photoshop color settings for image revision

3. Photoshop export settings

ACR Settin

When you open a RAW file image with ACR, there are two options shown above, taking the PS2021 version as an example, the upper one and the bottom one, which need to be set.

First look at the upper options, there is a key parameter, that is, the cache location, which directly affects the synthesis operation in ACR. ACR can carry out exposure synthesis and panoramic pick-up. Sometimes the temporary storage disk is full when using ACR synthesis. This is the problem here. So you should choose a location with more space for caching. It is best to set the cache space above 50g.

In the options at the bottom, there are three key settings:

Color space, color depth, resolution.

Let's say one by one.

1. Color space

The color space is divided into:

Standard RGB (sRGB)

Adobe RGB (aRGB)

Prophoto RGB

Prophoto RGB has the widest color gamut, but it is rare, and our display does not have a description suitable for Prophoto RGB, so it is generally not considered. SRGB has the narrowest color gamut and is generally used for Internet image preview. The color coverage of Adobe RGB is wider than that of sRGB, and Adobe RGB or Prophoto RGB color gamut is generally used in post-revision, because the wide color gamut can cover more color range, closer to the color information of RAW format in the camera, and avoid losing the color of the original film in the later revision.

2. Color depth

The setting of "color depth" is divided into 8 bits and 16 bits, which actually means that the number of color types of the image, the more the number of color types, the more delicate the color, this setting can be used to prevent the color fault of the image, because the reason for the color fault is that the degree of color fault is too large in the later stage, so that the color you repair can not be displayed. If you choose the color depth of 16 bits, you can show more colors. It is not easy to have a color fault.

This is the relationship between the power of 2, 8-bit channel is 2 to the 8 power, equal to 256; here refers to each primary color can be divided into 256 colors, then there are three primary colors, a total of 256 times 256 times 256 equal to more than 17 million colors; 16-bit channel is 2 to the 16th power, in the same way, after the multiplication of three primary colors, there are hundreds of millions of colors.

The parameters on the display are actually based on this setting. The color depth of the display determines the fluency of the color transition of the display, which is generally expressed by the number of bit. To put it simply, the higher the bit value of the display panel, the more the gray class, the more colors can be expressed, and the more uniform the color transition is.

The display with 8bit color depth is only enough for daily office use, the photographic revision requires high color, and the color depth of the material photographed by the camera is mostly 10bit up, and the 8bit display is not enough. My bright base SW270C display can reach 10 bit color depth, 1.07 billion colors, can show more colors, more delicate, more smooth color transition.

3. Resolution

In the process of image revision, the resolution should not be too high, because the larger the resolution, the larger the image space, which will seriously affect the processing speed, so the moderate resolution is good. Usually I choose a resolution of 300. This resolution is sufficient for network sharing pictures and printing less than 20 inches. If you need to print a larger picture, you can change the higher resolution before exporting.

After the PS color settings enter the Photoshop interface from ACR, there is an option of "color settings" in the "Edit" menu bar at the top, as shown below:

Select "Custom" in the red box in the upper left corner of the image so that the data settings below will be applied. Many beginners use "Japanese General use", which is a built-in color preset, so no matter how you set the data below, it won't work.

RGB color space usually chooses Adobe RGB 1998, so that you can get enough color gamut when revising the picture, and you can also set Prophoto RGB, but the monitor also has only Adobe RGB color gamut. As for the chromatic aberration when exporting the picture, we set it when we export it.

Color management programs are selected to "convert to work", so that the images will be converted in accordance with the settings in PS, to achieve our unified standard, if you choose to "retain embedded" it is still the information of the picture itself, can not play the role of PS.

PS export settings when exporting, the following settings can reduce the image chromatic aberration problem. After entering the Photoshop interface from ACR, there is an option for "conversion profile" in "Edit" in the top menu bar, as shown below:

Click "Color profile" and the following interface appears

Select "RGB", and the configuration file selects "sRGB1966-2.1" as shown above, and check this option each time before exporting the image. If the conversion is successful, when you save the picture, it will be shown as follows:

This option will be displayed when saving photos, which is the configuration file you converted before. Be sure to check it. The Windows system is "keep ICC files". Only in this way can the color information be stored in the picture so that other people's mobile phones or computers can recognize and display the color correctly. If you print it, the professional printer will also recognize this data.

This is my bright base SW270c monitor with flocking shade and OSD controller.

This is the standard OSD controller for setting quick adjustment items, such as display color mode switch, black and white switch, dual RGB mode, etc., as well as quick brightness adjustment and contrast adjustment.

I use the Apple Macbook Pro external monitor. I usually take my laptop with me when I go out and connect it with my monitor at home. Because the 16-inch laptop screen is too troublesome to look at for a long time, I want a larger monitor to repair pictures at home.

This article is from the official account of Wechat: light and Color World of Shadow Leaf (ID:wangyikai-2016). Author: shadow Leaf.

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