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In movies, there are certain types of scenes where an actor/actress is standing facing the camera, in a hallway for example, and the hallway (or environment) is extruded or seems to get longer.
I want to use LOTR as an example, when Frodo, Sam and the other two just got finished running from the farmer and they landed on the road. Frodo got spooked and when he looked down the road, it seemed to grow longer. He yelled at them and they hid under the tree.
What is the name of this effect?