Calibrating Displays For Color Accuracy
Your display tells a story about your images. In order to get the best quality, the display must not only be high resolution, it must be properly calibrated for color accuracy and brightness. This is not so much for the average user. This does become important for professionals who work with graphics, video editing and retouching in post. The typical display that most are familiar with, is the computer monitor (which we shall cover). Other displays include screens on smartphones, televisions, tablets and laptops. Depending on which display you are working on, having it properly calibrated allows you to have the most accurate color reproduction on screen. This becomes important for commercial work, like shooting photos for e-commerce and print catalogs.
When a designer wants a photographer to display their work, they also expect accuracy in details. Those details include the color in the image. Sometimes the colors do not match what is on screen from what the people see in the real world. This will become a problem especially when color is an important part of the product. You cannot really sell an item that is described as ‘red’ but doesn’t quite look red, let’s say it looks more ‘orange’. Inaccurate colors can really ruin it not only for the photographer, but most importantly the designer. To prevent this from happening, the process of color correction and management becomes important. In order to do this, both the software and hardware must be properly configured. For displays this requires color calibration.
Calibration Basics
Well calibrated displays provide the best results when it comes to quality, color and brightness. It begins with creating a profile that best suits the needs for color accuracy that the workflow requires. This is the process of color profiling the display.
The following are the basic steps when performing a calibration:
- Set Target Color and Contrast. When profiling a display, these are requirements. The display in this case is usually set to mimic the color of daylight.
- Set the White Point to 6500K which is the color temperature of daylight.
- Set the Gamma to 2.2, Windows or TV Standard.
Target color refers to the palette for the profile. This forms a part of the ICC (International Color Consortium) profile that stores the information for the display. There are many types and these are also called color spaces. When taking this into consideration, we must reference the RGB color scheme. Common color spaces include sRGB, Adobe RGB and ProPhoto RGB.
Contrast is the difference between colors. When you have contrast you can distinguish the whitest white and the darkest blacks. In terms of light, contrast can be the measure of brightness as it differentiates the lightest from the darkest.
White Point is a reference for daylight in color. It is the point where coordinates in the chromaticity scale converge to the color white. In profiling, the D65 White Point is the color of daylight.
Gamma refers to the tone curves. When adjusting gamma, it can be described as the measurement of contrast that affects the midtones of an image. Gamma correction uses a mathematical formula that adjusts the levels of dark and light in relation to the contrast in an image. It can bring out the darker colors which can also increase saturation.
Display Consideration
The following things can be considered before calibration.
- Turn on the display and leave it for 15–30 minutes to allow it to warm up to its normal operating temperature.
- Set the default screen resolution. See your monitor or display screen’s document user guide for more information on how to do this.
- Avoid too much brightness and glare. If your room is too bright, pull down the shades. A darker room, no windows would be ideal. The important thing is not to allow too much light to overpower the display. You would want to see the display in its actual specifications.
Display Control Calibration
The easiest way to calibrate the display, like a computer monitor, is to use the built-in controls. You can locate these controls on the front of the monitor, while on other displays you will need to dig deeper into the settings. These controls allow users to adjust brightness, contrast, gamma and saturation. An automatic setting is the default configuration, but users are allowed to change them. Many displays also come with menus that allow users access to more specific settings for configuration (refer to the user manual of your display).
While these calibration settings are sufficient for average users, it may not be adequate for professionals. That is why there exists other tools, both software and hardware that allows more accuracy and control of calibration.
Software-based Calibration
You can calibrate your display using software and you already should have it on your computer. Operating systems like Windows and the macOS provide ways for users to adjust their display’s settings. These built-in calibration tools provide a process of monitor calibration for those who have a fair or low budget. This is for amateurs and professionals who produce content, but don’t require high-end accuracy. This is because color and brightness itself can be subjective, and to get the most pinpoint accuracy is not something that can be achieved unless you have the budget and equipment for it. For most creatives who work with web content, this should be sufficient. The Digital Trends website provides a guide on how to calibrate a monitor using Windows and the macOS (follow this link).
Other means of software calibration includes actual software tools that are not a part of the operating system. These tools may require installation or may require plug-ins or add-ons (depending on browser). Others are web-based. They can provide precise and customized calibration settings, but each tool will have their own set of features. Examples of these online tools include Photo Friday and Calibrize 2.0.
Simple color correction can be as simple as adjusting the color balance or temperature, but it does not genuinely show preciseness when it comes to accuracy. While it may look correct on the retoucher’s screen, it will not appear the same on other people’s display. That is why there are other more precise color calibration tools that are hardware based for that purpose.
Hardware-based Calibration
For more professional commercial quality results that require the highest accuracy, there are hardware tools available. These calibrating devices can be expensive, but they do provide the best results for reading color accuracy. They are actually sensors used in coordination with software for profiling displays, so they don’t adjust the settings automatically. They first need to measure the color output and signals.
Some common type of hardware based sensors include the following:
Spyder 5 Pro (Data Color Spyder Series)
Colormunki Photo (Xrite)
These products works with software utilities that provide easy to follow steps using wizards. They also include automatic profiling modes that sets the White Point and Gamma (daylight and 2.2). More advanced features for target color are available for precise calibration. This should meet the needs of more detailed imaging professionals who need it for commercial work like cinematic film, commercial advertising and online catalogs.
Color In Print
The process of color in print is much different than content on the web. This requires creating printer color profiles which use printer specific color schemes. Printing technology use different types of pigment and materials for color in ink and toners, so the color on screen may not match the color on print. For this to match, the printer must have driver software that includes a color profile which is supported by the printer.
Summary
Calibration allows users to make the best use of their display’s capabilities. Making use of the features of a display provides the best image quality in terms of color and brightness. It is important in commercial work because getting the proper colors to display will be important for the final result. Use the appropriate color calibration technique for your digital workflow.
