If I took a shot of a mountain and another guy came in the same spot, or happened upon the same spot and shot the same mountain is it infringement?
There was a case in the US where a photographer took a cityscape from a famous landmark at a very specific point of sunrise that captured a very unique effect as the rising sun struck various landmark buildings. That image got widely published.
Later, another photographer took an identical shot from the identical position at the identical sun angle. A court ruled it to be copyright infringement. The court's opinion was that the second photographer didn't just happen by chance to shoot from the same vantage point. The court believed it was an undeniable attempt to duplicate the first photographer's image--a copyright infringement.
There was another case in France in which the tourist ministry of France published a photograph of a couple on a carnival carosel. The wide-angle shot was of a woman in a polka-dotted frock sitting on the hobby horse on the left of the image with a man in a dark suit and tie on the right of the image. An editor at Getty thought he recognized the image as one of theirs, but didn't recall having sold anything to the French tourism ministry. He checked their files and did find a shot, a wide-angle view with a woman in a polka-dotted frock on the left sitting on the horse with a dark-suited man on the right. The posing was virtually identical, although obviously the models were different. A French court ruled it a copyright infringement in favor of Getty.
It very much depends on whether the court can be convinced the second image was a deliberate attempt to duplicate the first image. You can't copyright an idea, but you can copyright a specific implementation of an idea.
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