Monitor Calibration Devices
Monitor calibration devices allow both calibration and profiling. Most calibrators look like a computer mouse and attach to the display. Included with the device is a program that displays on the monitor a consistent set of colors and tones that are measured and recorded by the device.
The most common calibrators are:
Rite Eye-One Display,
ColorMunki Photo.Calibration should begin 10-15 minutes after turning on the monitor to allow it to warm up. This will ensure stability of brightness and color balance. Next, you will need to set the monitor parameters for calibration. These parameters include white point, gamma and brightness. During the setup, you will need to change some monitor settings, including its brightness, contrast and RGB values, if you are using a CRT.
As a result, you should get a matrix of color values and their corresponding parameters. The device will create a Look-Up Table that will reproduce neutral and accurate shades of gray, as well as matching hue and color saturation.
There are several parameters whose values must be determined to calibrate the monitor.
A white point is needed to determine the warmth or coldness of the lightest tone of the display. Increasing the color temperature allows you to get colder tones, and its decrease is warmer.
The standard recommended temperature for a CRT monitor is 6500K (or D65). It is slightly colder than normal daylight. Setting up LCD monitors is more complicated due to the fact that their backlight always has its own color temperature, which cannot but affect the image. In this regard, it is usually recommended to leave the color temperature of LCD monitors unchanged, unless you clearly need to change it.
Gamma controls the rate of increase in the brightness of the shadows when switching from black to white. It has a significant effect on the contrast of the image, and also makes it look lighter or darker.
Currently, the standard for editing and viewing images is a gamma coefficient of 2.2, which is closest to the monitor settings, as well as to the human perception of brightness variations.
Brightness determines the amount of light coming from the monitor. The setting of this parameter depends entirely on the level of illumination of your environment, including daylight or electric light in the room, as well as its additional sources. The most common value for this parameter is 100-150 cd / m2, however, if you work in a room with strong lighting, you will need to change the brightness of the monitor.
How the Look-Up Table Works
The LUT is controlled by the video card or by the monitor itself, so its use does not depend on whether the software supports color management. LUT loading begins immediately from the beginning of the operating system, and its use is carried out, regardless of what is on the display.
To better understand how LUT works, take a look at how different the gray color may look like, which should be displayed on the monitor when the values of red, blue, and green are equal. The objective of the LUT is to maintain the gray tones in the correct gamut.
In some cases, several LUTs are involved in creating the image on the monitor, and not just the one in the video card. Especially clear calibration can be achieved using the adjustment built into the LUT monitor, but not all models allow this.
What is the color profile for?
The color profile is necessary to convert images so that they are displayed as correctly as possible, taking into account the characteristics of the monitor. Unlike LUT, which starts immediately after starting the system, in order to use the color profile, appropriate programs that support color management are required. For this purpose, you can use Adobe PhotoShop or another program to edit images or work with the RAW format.
Each time the program opens an image containing a color profile, the program compares it with the monitor profile and, if there are differences between the color spaces, it converts them.
How to check the quality of calibration
Not always the device can perform its task efficiently, so every time after calibrating the monitor, you must check how it was carried out. And even if you find that your monitor cannot be configured better than this calibration device did, you can take this flaw into account when editing images.