What do you mean by effective? FLIR's support told me it can pick up the heat signature of a person at 100 meters. I went outside earlier and it seemed alright at a long distance. It's not like it simply doesn't work after 15'.
I think due to the resolution many of the interesting things you can do with it will end up being at short range.
I also noticed it reports the sun's temperature as "> 212ยบ F" so there's that.
I didn't get a quantitative definition of effective, I asked how far it would detect a heat signature, they said 15 feet. I'm sure it "works" at greater distance, the question is how much noise you get and how reliable it is at greater distances.
They had one on site and the reason I asked the range was because I held it up and looked and it seemed very very local. I'd be happy to see this thing produce a heat signature that you can identify as human at 100 yards, that isn't the same as a human's heat signature at 100 yards though.
I think due to the resolution many of the interesting things you can do with it will end up being at short range.
I also noticed it reports the sun's temperature as "> 212ยบ F" so there's that.