I may be mistaken, but I am not sure there are any cameras that can record at 240fps at 480p. Inexpensive cameras trade off resolution for speed, because the chip inside the cameras are not powerful, and high fps eats up a lot of memory. I think the best you can expect at 480p is 120fps.
Films you see with high quality slow motion video are either made with specialized high speed cameras, or created after-the-fact in processing with programs such as Final Cut Pro.
I do not know anything about them, just want to use it to record a pitching motion. Probably will not take any pictures.

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