Linn,
I've run across a seller on eBay calling themselves "Steam Engines 2 Go" who sells 8x10 prints of various steam locomotive images. I recognized at least one of the images as being taken by your father, but not credited to him. Now I don't know if you (or your dad) allowed him to sell these pictures, and if they are authorized to do so, I apologize for bothering you. But, if they do not have permission to sell your dad's images, I thought you might want to know. Here's a link to the image that tipped me off...
[
www.facebook.com]