A crude shot with my digital camera is perhaps not the best demonstration, but you get the picture. When running the calibration, you place the sensor in the middle of the screen.
These measure color output levels and relay them back to a software utility that records them and generates a calibration profile.
Given that this attention to detail for manual calibration can be frustrating to many users, an easier, more repeatable, and perhaps more accurate method for doing this is to use a hardware-based calibration tool. Both of these methods will work, but you will have to be aware of subtle color differences have the patience to adjust output levels while squinting and blurring your eyes to ensure accurate results. While Apple's calibrator works on various grey levels (performing the calibration on multiple colors at once), others such as Berg Design's SuperCal may do individual color components separately. This in essence measures the color output with respect to the black level of the display and allows you to get a good reference for intermediate intensity levels when calibrating, even though it sometimes requires you to do a fair amount of adjusting to ensure accuracy. These usually require you to first set a proper maximum brightness and contrast of the display, and then compare a generated output level (the color in the Apple symbol) to a color that is half it's strength (represented by a pattern of alternating black pixels). Apple's built-in calibrator in the "Color" section of the "Displays" system preferences is an example of a software-based color calibrator. There are various ways to create calibration profiles, with the most common being either software-based calibration utilities or hardware colorimeter devices.
Apple's calibrator can be found in the "Displays" system preferences. Luckily this can be corrected by creating a calibration profile that will adjust the computer's color outputs so the display's response is linear and at the proper intensity levels to generate expected secondary colors when primary RGB components in the pixels are mixed. These varying output levels will differ for different monitors, and result in colors that are slightly off from each other.
This means that, for instance, if the computer outputs a half-strength signal for the red channel, the monitor should also output 50 percent of its maximum red intensity however, most of the time this is not exactly true, and monitors will output maybe 47 percent or perhaps 51 percent of the maximum output. This will not only allow you to adjust the richness of the colors on screen, but also allow you to have the colors appear uniformly across different monitors and output devices, which can be especially useful if your work involves design, photography, or otherwise depends on proper color matching.Ĭalibrating a display is essentially adjusting the output for the individual colors (red, green, blue) across various light intensity levels to generate a correction curve for those levels. One of my recommendations whenever anyone gets a new computer or more specifically a new monitor is to calibrate the display so colors appear properly and as expected.