The phrase "monochrome mode" refers to a setting or feature that displays only one color, usually black or white, on a device or screen. Full definition
And this results in some stunning low light photography, as the sensor simply is able to capture better images with lesser noise when in monochrome mode. (techpp.com)
One of the most effective ways to utilize that secondary camera is with monochrome mode, as it takes what the sensor is made for and turns it into a dedicated mode. (androidheadlines.com)
Unlike the Honor 8, thankfully, the Honor 8 Pro has a dedicated monochrome mode that allows you to use the monochrome sensor to its full extent. (androidauthority.com)