Some very interesting shots, including some very rare color for some older things like the P5 electrics. Thanks for posting.
While it is true that an older generation of PRR models such as Athearn's are way too green, I am not sure I would draw too many conclusions about Pennsy green from color slides however, or for that matter, almost any railroad color. I have non-PRR photos that I took, and photos from collections that I have acquired, where locomotives of presumably the same color look very different parked near each other or combined into a consist. Dye lots of various paints followed the same forumula but there can still be differences -- as any avid knitter can tell you.
Slide films of various makes have or had their color biases. so to speak, and as the film ages (and Kodachrome ages very slowly thank heavens), there are still more shifts, and finally there are color biases in the slide scanners and other technologies.
It is interesting to see a really great color photo of a Pennsy "green" locomotive next to something truly and unquestionably "black." Only the presence of the truly black freight car or locomotive makes the green evident, but it is evident.
Dave Nelson
This is a narrated slide show. Great photos of '50s and '60s PRR scenes mostly around the lines east, some Pittsburgh, some in Ohio.
Lots of modeling ideas. I watched it in bits and pieces. I did come away with the conclusion that nearly all my HO PRR locomotives are a) too green and b) not weathered enough.
PRR_9616-FA2x by Edmund, on Flickr
Good Luck, Ed