Iim looking for a book, chart,etc that will give some general insight into the slection of Base Curves and thus ocular (back) curves which gives more comfortable vision for the patient depending on his/her prescription. I understand that in the past few years we gone away from the traditional curve charts in favor of the flatter European curves. The lenses look better but where is the limit/or is there a limit? Recently the Retailers are asking that Rxs be put on what ever curve is available-------but does this result in good optics for the Patient?