"Vantage point" is the term used to describe the view from the camera’s lens in real space at the same location from which the original photograph was taken. The vantage point gives the repeat photographer the truest link to the initial photographer’s now invisible footprints, in order to see the object or place to be captured from as close a mark as possible to the original perspective.
"Viewpoint" is the relationship the photographer has with the place being photographed. It is different from the vantage point, as it is not part of the technical, concrete process of making a photograph. Rather, viewpoint is a mixture of elements coming from the photographer that add flavor to a photograph. Elements of the photographer’s artistic style, opinions, and relationship to place and history may come into play and affect the re-creation. Viewpoint brings to the surface issues such as: Does the repeat photographer want to purely duplicate the original photograph? Or is the goal to create a new photograph from the same vantage point but add commentary in some way regarding the changes that have occurred? Background knowledge, or lack thereof, regarding the original photographer’s purpose or agenda in taking the photograph in the first place may influence the modern photographer’s perspective.