the effect is one that makes balls roll up hill and people refer to feeling g forces on them making them move in different directions I am sure most of it is forced perspective but don't know how to do it
Knotts Berry Farm used to have one of those "haunted shacks" (don't know if they still do), and it was one of my favorites.
It takes a combination of things for this one to work.
As you mentioned, forced perspective is one.
Another is the surroundings - even though all these rooms are built on a hill, the walls and doorways are built at a right angle to the slope of the hill, not to gravity...and there is never a window or doorway that allows a view to any horizon. Since the eyes can't find any outside benchmarks for what is "level", they begin to take over from the inner ear, and perceive the room to be "normal" (well, normal"er" than it really is) - this is why things appear to move uphill, and someone can sit in a chair that's just resting on a shelf on the wall, without toppling forward. Even though the pitch of the floor may be significant, the brain begins to believe it's just a slight angle, so these "miracles" become believable.
Finally, the power of suggestion. You have to keep up about the "mystery" and "anti-gravity waves" and "haunted forces" that power the place. This, along with the un-noticed confusion people have from the angle, and lack of outside reference, will give the mind it's "answers", when it can't make sense of things.
Here's a pic I found that gives an idea of what I'm talking about:
Knotts Berry Farm used to have one of those "haunted shacks" (don't know if they still do), and it was one of my favorites.
It takes a combination of things for this one to work.
As you mentioned, forced perspective is one.
Another is the surroundings - even though all these rooms are built on a hill, the walls and doorways are built at a right angle to the slope of the hill, not to gravity...and there is never a window or doorway that allows a view to any horizon. Since the eyes can't find any outside benchmarks for what is "level", they begin to take over from the inner ear, and perceive the room to be "normal" (well, normal"er" than it really is) - this is why things appear to move uphill, and someone can sit in a chair that's just resting on a shelf on the wall, without toppling forward. Even though the pitch of the floor may be significant, the brain begins to believe it's just a slight angle, so these "miracles" become believable.
Finally, the power of suggestion. You have to keep up about the "mystery" and "anti-gravity waves" and "haunted forces" that power the place. This, along with the un-noticed confusion people have from the angle, and lack of outside reference, will give the mind it's "answers", when it can't make sense of things.
Exactly. The power of suggestion really can elaborate upon the optical illusions in such "mystery spot" style attractions, producing a pretty amazing experience.
And I'm sorry to report that Knott's Haunted Shack was destroyed back in 2000 to put in another stinkin' (and short-lived) Cedar Point copy-cat thrill ride, in addition to attendance and accessibility issues. In case you can't tell, I'm still very bitter about this .
OMGosh I remember that darned shack at KBF - it freaked me out as a little kid. I have no clue how they did it but kind of like trompe l'oeil I would suspect. Good luck!!
Hubby just brought up an interesting idea on how it worked - the room was built "bent" one direction and the items in to were "bent" in the opposite direction.
It's all about aspect as described. Mystery Hill here in Michigan does it. It is built on a hill, and the walls are built at a 90 degree angle to the hill, therefore being tilted. There is an outer shell built straight up to "fool" your eyes on the outside. When you walk in, it feels like you're being pulled towards the wall. HOWEVER, if you can see outside, the effect is IMMEDIATELY gone. It's really weird. This is why the doors are angled so you don't just walk straight in. You have to go around the barrier. At one point I was "holding myself up," then looked down the hall and could see outside, then suddenly, the effect was gone.
Regardless of how easy it is to achieve, it's really a kewl effect!