Nik Silver Efex
If you’ve spent any time trying to simulate the look of monochrome (aka black-and-white) photography the first thing you realize is that it’s not a simple matter of taking a color image and desaturating it. There’s a lot more going on.

Test of blog image
Producing a convincing black-and-white image requires (at least to my mind) simulating the film and paper used to print it. Doing this manually would demand an enormous amount of time and experimentation.