The Power of Black & White

Every now and again I go back to the beginning, breaking an image down to it's composition, how the eye moves through an image and where it settles. Black & white is the best way to explore those properties in a photo, taking the inexact psychology of color out of the exercise. 
As a digital photographer I work in Adobe Photoshop and use calculations to make my black & whites from an original RGB color image.
If you want to know some tips in calculations, I'll be happy to provide an expanded answer.