One of the myriad joys of Ebay is how easy it makes collecting vintage photographs. You can pick up entire family albums from the 20's and 30's for a pittance, and you'll almost always score a few that are suitable for use as props as-is or with a little retouching.
Old black and white shots have an inherent creepiness that's hard to describe. There's an inescapable sadness in the fact that the people you're looking at are long dead, surviving only in the memories of their families and the piece of paper you hold in your hands. It's a concrete reminder of our own mortality, and as such invokes an emotional response on a very basic level. Re-purposing that unease to enhance the immersiveness of a scenario can produce some effective results.
This particular photograph was part of a lot from Postville, Iowa that I purchased earlier this year. As soon as I saw it I knew it would be perfect as a portrait of an Innsmouth hybrid starting to show the first signs of the inevitable change into a Deep One. There are three versions here. The first is the raw image exactly as I scanned it, the second a slightly cleaned up version for use as a contemporary photograph, and the third has been mildy retouched to enhance "the Innsmouth look".