Pure focus. Since focus is such a primary factor in photography, I wanted to consider just the quality of an image in and out of focus.
This sequence explores both light-on-dark and dark-on-light subjects, how focus affects size of image, and whether focus in front or behind the subject matters. Due to optical laws that are entirely beyond me — changing focus also changes the size of the subject. In the white background sequence, I allowed the size differences to show, but in the black background sequence, I adjusted the sizes so they match and make an easier comparison.
Bottom Line: There are infinite subtle variations in the quality of soft focus, and those qualities make a great deal of difference, even if it is the background that is out of focus.
100mm, f16, flash, ISO 800