What can FLIR 'actually' see?

Hi,

I had a fierce discussion with a friend, and we couldn't come to an agreement on the topic. I need your knowledge/expertise to set this straight.

The topic: Can FLIR/IR/Thermal Camera's actually SEE hot air? For example when it is coming out of a chimney (exhaust).


My opinion: They can't. As far as I know, thermal camera's can only 'see' the temperature of physical objects. As AIR is not something 'tangible', they can't see it.
My friend's opinion: They can. They will see the hot air coming out of the chimney like some kind of volcano under thermal image.

Who is right?


In my opinion they can see it only like this:

>> so they can see the chimney itself has a higher temp due to exhausting the hot air through it. But this should be 'normal' for a chimney, no? I mean, if you have a fireplace your chimney will probably look the same on thermal.


He claims it's looking like this:

>> I told him, on industrial chimneys there is actual smoke which may contain 'hard' particles or actual 'fire' coming out, that's why it is visible there like that. On grow room exhaust it's only hot AIR coming out.



Due to 'our hobbies' many helicopters are flying around and he claims they see the exhaust and can catch you by that. I claim they can see only the roof temps, and only if your 'room' is poorly isolated, they can spot you. So who is right and who is wrong here?

I don’t think they can see the air, but they will see your grow room hotter than the rest of your house and anything that hot air exhausting is coming in contact with

They can only see ir light as heat. Not hard to evade with space blankets on the cheap over a moving blanket. Not any warmer than native foliage if outdoors. Only a threat indoors. LOL.

GeneBanker said:

Click to expand...

Thanks this solves it for me.

We both have tents inside a room which has proper isolation and also an anti-detection foil applied all over the room as "wallpaper" on the walls/ceiling for double protection. The outside of the house walls and roof temps (measured with IR guns) are all the same. Only the chimney itself is "warmer", but I guess that is something 'they' don't really pay attention to. What do you think?

If no one else's chimney is glowing on thermal and yours is it's like a beacon to the police your pumping hot air. If they understand the concepts you can get a follow up.

If you grass here the police sweep your house next time the chopper passes, standard procedure for a lot of the UK. No small grows show and it's back to ground work.

You don't see the air but that video shows how sensitive and the air soon changed to purple and just a short blow on the wall was crazy bright.

Depends on a lot of things, I wouldn't worry, buy a drone attach thermal, see for yourself.

BBQtoast said:

If no one else's chimney is glowing on thermal and yours is it's like a beacon to the police your pumping hot air. If they understand the concepts you can get a follow up.

If you grass here the police sweep your house next time the chopper passes, standard procedure for a lot of the UK. No small grows show and it's back to ground work.

You don't see the air but that video shows how sensitive and the air soon changed to purple and just a short blow on the wall was crazy bright.

Depends on a lot of things, I wouldn't worry, buy a drone attach thermal, see for yourself.

Click to expand...

Are your heating and cooling systems that primitive? Honest question. My chimney vents my hot water heater only for about 15 years. I uess the wife and kid draining the tank would be an alert. JK. Feel for you. Our helis use a vapor imaging for outdoor grows. Utility company was only other fairly accurate detection here. Prior to internet and digital drivers. More than helis and cameras to consider if you need to consider such things. Be safe.

MICHI-CAN said:

Are your heating and cooling systems that primitive? Honest question. My chimney vents my hot water heater only for about 15 years. I uess the wife and kid draining the tank would be an alert. JK. Feel for you. Our helis use a vapor imaging for outdoor grows. Utility company was only other fairly accurate detection here. Prior to internet and digital drivers. More than helis and cameras to consider if you need to consider such things. Be safe.

Click to expand...

Everything is different everywhere, it's not a worry to me or most but just highlighting possible problems.