I rode the roller coaster at CosmoWorld in Yokohama and as it got underway, I and a few other people pulled out cameras and started taking pictures. We got to where the coaster begins to climb the hill, and it suddenly stopped. The next thing I knew, a rude man had come alongside the coaster and started confiscating people's cameras! I reluctantly allowed my camera to be stolen, but it completely ruined not only the ride, but any enjoyment I would have had that evening.
Not being complete and total thugs, they returned my camera at the end - complete with greasy fingerprint on the display screen. [Note to CosmoWorld camera thief:
1) You shouldn't physically touch the display screen in the first place, and
2) Try washing your hands with soap dude - it's gross having personal property not only rudely stolen, but greased up with your filthy hands!]
The thing is - I don't recall any obvious signs about "No Photography!" or any clear announcements saying "No Photography!" and then they stop the ride midway and send around a rude man to steal people's cameras. It may say something somewhere and they may have said something in the mumbled announcement before the ride, but it wasn't noticeable, and if they're going to steal people's cameras so rudely, they should make it very clear that they are fanatical about no pictures.
The ride turned out to be very boring anyway - too slow, boring, and over too quickly. That may be why Yokohama's CosmoWorld doesn't want people taking pictures/video - as it would be apparent how very boring the ride is and how it's definitely not worth the Y700 they charge for it.
So, I would advise anyone visiting CosmoWorld in Yokohama to avoid the "Diving Coaster - 'Vanish'" ride, or - if you are determined to ride it - then keep your camera hidden until the ride is at the top of the first hill and about to begin coasting down, a point where I don't think they can just suddenly stop it and send a rude man to climb the hill to steal your camera.