How do i tell if graininess is from film or from TV?

[Valkyr47]

Im aware some HD movies have a decent amount of grain in them, sometimes on purpose as a way of being artistic, other times just because of the way the film was shot or limitations on equipment

grain doesnt bother me... as long as i know its in the film itself and can not be avoided in any way possible.. the reason i get so antsy when i see grain is because for all i know it could be from my tv

I will be honest, i didnt have a ton of money for a tv and i went the cheapo route, got the very bottom rung Sony Bravia (KDL-46S4100) its not rated very highly and i know i should not expect the best, but i wanted a 46" screen and the 1200 price tag was all i could spend

i will admit my blu ray player is probably also not of the highest quality, i just grabbed a sony bdp-s350 for 300 bucks from walmart, where i got the tv too

that being said, how can i tell if it is the movie that has the grain, or if the grain is from the TV because its a cheap one?

i noticed that if i pause the movie, the grain stops moving and gets paused with the rest of the picture, does that answer my own question?

thanks!