On the contrary, not all of the pictures are real. There is one I'm aware of that is a picture of two identical sirens placed next to each other, mounted on a platform between two poles. It was clearly a copy-and-paste job in photoshop, and a close inspection of the pixels on each siren confirmed this.
While manipulating photos is fun and interesting, LIFA makes no attempt to inform the viewer of altered material, instead just throwing it in the mix as if it were authentic. I haven't combed the whole site for frauds, but I would not be surprised if more showed up.
The owner has already showed us at least one fraudulent photo, one blatantly stolen recording, and had submitted a doctored sound clip (cheating) to the siren recording contest in 2004. This guy's credibility has deteriorated significantly in my eyes.
Proud owner of a bunch of cool stuff.
I'm 447 years old!