I breed king, corn and rat snakes. I breed for color and pattern. I can get that blotchy pattern and the colors of the snake shown (which was ready to shed within a few hours - eyes aren't blue anymore). But that is NOT a corn snake. In fact, I don't think you'll find corns to be native to central PA.
As far as a copperhead. Not sure there either. Head shape is wrong and eyes are wrong. If it is native to that area it does make it possible though.
I'm going to throw a wrench at this and say it is probably a NORTHERN WATER SNAKE. Similar markings, similar shape, similar size to a copperhead. I believe they have known to have red eyes and are found in central PA. FYI, they are a very aggressive and will repeatedly strike just-for-the-heck-of-it. Total pricks.
IMHO, I'd say I'm 85% sure it is a northern water snake. 15% could be a copperhead and no way a corn. I know snakes fairly well but not so much with copperheads 'cause they aren't found in my area so I'll leave it open that I might be mistaken.
I hope that helps.