For many photographers, particularly hobbyists, making an image black and white is almost arbitrary. I remember in the early days of my photography, I was the same. I would mutter: "I wonder if this would look good in black and white," and then, I'd try it. Sometimes, it would look better, but usually, it would not. I presumed it was all just down to taste, but that's not true. After years of reading around the subject and experimenting, I began to understand why it worked when it did and conversely, why it often didn't. Here are some key elements that ought to be present in black and white images, and why.