There is little ephemeral about the materials and construction that went into the Kodak Professional Photoguide. In fact, the sturdiness of the Photoguide allowed it to survive far beyond its useful life. Film types included in the tables disappeared along with technical practices that were superceded by microchips. Of course, some useful data remains. I brought the booklet home from the used bookstore for the calculator it contains to determine exposure with my old Kodak Recomar 18 when the bellows is extended for macro capability. Beyond that, the remaining value of the guide is in the extraordinary graphic design.