Warren, you get out to some interesting locations. Thanks for posting these. Oh, what we might give to have stood on that bridge with a camera in 1955!
Personally, I've never taken any train photos in the east except for a few around Boston in an urban setting. The photos you posted illustrate the heavy growth of trees that is so common in the east. You managed to work with the light and the shadows and get nice overhead photos from a nifty-looking bridge. 
Guys I know from the southwest, who have photographed trains in New York and Pennsylvania have told me that you have to know your territory, as you can often hear the trains but you can't see them. You really have to know where to be in advance, and how to find the railroad if you want to shoot the same train in more than one location. You obviously know the way to do that.
Out here on the high plains, we have different challenges when photographing trains. This part of the country is grassy and almost treeless, so the sun is always on one side and the shadows are definitely on the other. Prairie is prairie, is prairie, and we have to find ways to keep the photos from all looking the same. And there's usually a wind blowing , sometimes annoyingly. You can't always find shade to keep cool between trains. But . . . sunrise and sunset, as well as the blue hour, are nice bonuses. There are not many overhead bridges, but we do have the option of shooting from a large perspective. And we don't have to fight black clouds of mosquitoes or get rained out very often.
Thanks for sharing these views of the former PRR.
Thanks Tom, I would like to go back to being there in 1955, but I was still 4 years in the future. The "West Slope" of the old PRR's climb over the Alleghenies didn't seem to get much attention until the Conrail era, as the Horseshoe Curve side (East slope) became less accessible because of trespassing issues, tree growth, and the change in Horseshoe Curve to a NPS site.
This stretch of track has not changed much since Conrail days. A goal of mine this year is to try to shoot NS trains passing the old PRR position light signals before they come down for PTC implementation.
I don't have any particular claim to fame for being a railroad photographer besides having a casual interest in geography and topography, I came late to the photography part of the hobby, (age 29), and was fortunate to have some good mentors early on.
My other main hobby is the photography of fire apparatus, not at fire scenes, but posed portrait-style photos. This photography requires 3/4 views in full sunlight, but unlike fast-moving trains, the fire rig is sitting still.
RR photography is more of a challenge for me particularly with the change from slide film in manual SLR cameras to the high-speed digital capability on my Nikon D7000.
The attached photo is c.1995, and shows a Conrail eastbound intermodal at Cassandra,PA., 1mile east of where I was last Sunday. This is the location of a Railfan park built around a former road bridge, visible is the aforementioned slide fence which caused the speed restriction last Sunday.
Note the various forms of intermodal on the train, IIRC this was not long after CR cleared this line for the double stacks in use at that time.
Photo by Warren W. Jenkins
