RWR wrote:
It can also be stated that the distance scale on a lens is the subject distance - subject-to-focal plane. I have some published tables for Leica lenses, when used with either extension tubes or Elpro close-up lenses, that give both the subject distances and the subject-to-lens (or Elpro) distances. For my own tables, I measure from the subject to whatever is on the lens, such as a hood, ringlight, etc.
You are saying that the "Distance scale" is the same as MFD (minimum focusing distance) and that "subject distance" is MWD (minimum working distance). I am surprised though that you measure from the top of your subject to whatever is on this element, e.g. filter, hood, ring-light) rather than the element itself and that, quite obviously, your subject remains in focus.