IR Pass Filters

[fubarhouse]

Hello all,

I'm curious about the whole IR deal, and not the real proper IR photography - as much as that is interesting. About seeing invisible things say washed out blood on carpet, seeing through fogs, seeing through some fabrics and such. The idea compels me - however I kinda don't believe it, as logical as the theory sounds.

I've read that the effect is only valid on Nightvision cameras, is this true? And how could I achieve the effect on a DSLR without the modification of the camera? I want to believe the theory but I don't know if i can, even though there's apparent photographic proof.

Thanks in advance.