Hey I am new and was wondering if there is some sort of schedule available for when trains will be passing through Newton Junction. I want to take pictures of trains there but I do not want to be that sketchy guy sitting in his car for hours on end waiting for a train.
Railfans aren't usually considered "sketchy," when sitting watching the trains roll by. As for a schedule, POSE/SEPO (POrtland-SElkirk/SElkirk-POrtland) runs fairly consistently with SEPO usually coming through Plaistow between 11am and 3pm. I'm not sure when POSE comes south through Newton Junction. Various other trains also run. I recommend investing in a radio scanner (~$100-200) which can alert you when trains are moving and where. Others may have more to add on that.
As always good luck, and don't be afraid to spend a few hours killing time by the tracks.