See this Apple support document for more on calibrating the displays of these Macs. Given the way the displays are calibrated, you can only perform this calibration with a spectroradiometer, an expensive device that most users don’t have. Note: the instructions below apply to most Macs, but if you have one of Apple’s M1 Pro or M1 Max MacBook Pros, with Liquid Retina XDR display, the process is very different. It’s easy to color calibrate your Mac’s display, and you can do so quickly by eye, or you can use additional hardware to get your colors exactly right. It does this by changing the intensity of the main colors - red, blue, and green - and setting the white point, or the neutral white color that you see when, say, you open a new document in a word processor. The calibration process tweaks a number of settings to get the colors and contrast on your Mac as accurate as possible.

However, if you work with photos or videos, or even if you like to watch movies in the best possible conditions, color calibrating your display is essential. If you only use your Mac for browsing the Web, sending and receiving email, and working in a word processor, it’s probably not that important for it to display accurate colors. How To How to Color Calibrate Your Mac’s Display

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