ok, so I don't learn something every day, but I learned something today. Black & White is different than monochrome.
The the site linked at the end here:
"...even though you may see these words used interchangeably, they are not identical!
The word monochrome means “of a single color.” So, monochrome photos can have a color tint, assuming it is just one color. Take a look at the photo below. It has a brown hue to enhance the character, but all the other colors have been removed. Although this counts as
monochrome, it is not
black and white. True black and white photos have no color at all. They are entirely black, gray, and white."
Comments welcome. Just as I was beginning to think that monochrome was the same as b&w.... Also, I guess Sepia is monochrome and not b&w....
Source:
https://photographylife.com/black-and-white-photography