i saw a flir camera being used in a documentary with the power companys copter:evilgrin0040:, they get a general heat source around windows as well as roofs, which they can change between 2 differant i.r colours black/white showed the whole roof differant colour to the surrounding houses roofs,they make it sound a lot more straight forward vthan it is, but i know they keep a few tricks up there sleeves but this wasnt as good as i had believed it to be, maybe massive grows yes ,but little house set ups in i.r proof tents no worries, im not saying dont take precautions because ive got my roof covered in it 2.0mx2.0m for £2.00 or £20.00 for all my roof and veg room wall.:sun thats the stuff Tex :bong-hits:white on the outside silver inside