Who knew that connecting your computer to your display using HDMI might be the reason your colours look bad and your prints look nothing like they do on screen? Here I explain why. The important thing to know is that it isn't the HDMI cable itself that's the problem, it's the HDMI settings. On some systems, for example with an NVIDIA graphics card, you can go into the settings and change them to give the full range of 0 to 255, but that isn't possible on other systems, including Mac. In that case, I'd advise using an alternative connection between your computer and display, such as USB-C.