I'm tempted to say that something about the grass makes me think it's film, but in all honesty I've never been able to tell with other people's pictures. I do know that the (non-people) images I'm choosing to print and frame for myself are almost all from film. That may simply be because I take more care with them, since each frame costs so much more (both $ and time).
But yeah, big trannies are great! I was wowed when I did some 6x9s a year or so ago, 4x5 must be amazing.