I have nine pictures all taken by Emil Kopac in 1931 & 1932. None of them show any people, but they are all dated and signed on the back with descriptions of the scene - all scenic spots in western US. One shows two large combines in a wheat field and says "operated on Kopac Bros. wheat farm near Oshkosh, Neb. Photo July, 1931 by Emil Kopac Oshkosh, Neb."
He was apparently a friend of my Grandfather Joe Vitek who grew up in Clarkson, NE. My mother remembers that he became quite wealthy from farming and spent time traveling around and sending pictures to his friends. Most of the people in Clarkson were from Czechoslovakia or, like my grandparents, from the Austro/Hungarian Empire because that is what it was before Czechoslovakia was formed.
There isn't much genealogical info here, but if any one would like a copy of the picture or writing on back, I'd be happy to send a copy.