Making Best Use of a Thermal Image Camera

[Ross365]

I have access to a thermal imaging camera (FLIR) but I’ve never had any training in its use. Going around my house with it, I’ve spotted areas where the loft insulation needed attention, and areas where there were significant drafts, but I wonder if I could learn more from it if I had the expertise? I know that you have to take in to account factors such as emissivity and angle of imaging to make sensible readings. Can anyone suggest more skilful ways of using a camera to assess home insulation other than just looking for the blue spots?

 

[gaz1]

take it outside and view it from there is the best coarse of action

same with the garage or workshop take readings when its warm in workshop and see how much your bleeding heat from those buildings

 

[Olderisbetter]

I was looking at some footage from a private investigators Flir and all i can say is if you are having an affair with a barmaid at night down a country lane be very scared

 

[willie.macleod]

Get the house nice and warm on cold evening then go out and you should get some good images.

 

[gaz1]

just so you know

 

[Ross365]

I was looking at some footage from a private investigators Flir and all i can say is if you are having an affair with a barmaid at night down a country lane be very scared

Many years ago, when the Warsaw-Pact was still around, I worked at the Plessey electronics company and they worked on a battlefield thermal imager. This thing was so sensitive it could detect the heat from a tank engine at some distance and even after it had been stationary for three days. The story that was going around was that there was a problem with it; if one of the men in the tank suddenly popped his head out of the hatch, this heat sensor could not cope with the intense radiation from the man's head and would burn itself out .

My house was built in the 60's when insulation was probably an afterthought and has an unusually shallow roof, making it harder for anyone installing insulation to get close to the eaves. It was very difficult to see from the central area of the loft that insulation was lacking around the eaves, but it stood out very clearly using the FLIR in the bedrooms.

 

[awemawson]

Back in the late 60's I was working for Mullards on multi-element infra-red arrays to go in orbiting space modules. These thing had to be cooled with liquid nitrogen to keep the back ground electrical (Boltzmann) noise level down so they had limited duration in space. We could detect the end joint of your little finger waggling at 1000 yards, and tell you (from space) if a vehicle had parked in a particular spot two days earlier. All frightfully hush hush, guards on the department doors etc.

We reckoned that if the Russians knew what we we doing it would set them back months

 

[voipio]

An emissivity setting of 0.95 is good for most things. Watch out for reflections from metallic surfaces. Copper pipes reflect well, even if they appear dull in visible light. To monitor the temperature of pipes, apply some black insulating tape. Flow problems from sludge in radiators is easy to spot. It's possible to work out where the central heating pipe runs are behind walls and under floors. Sky temperature varies a lot. Clear skies, even in daylight, can register below -40degC. Take a pee on a walk. The thermal signature will still be there an hour later! ;-) Thermal imaging car tyres after driving will show up tracking errors.

 

[Parm]

Consult google, then you tube

Seems to be the way these days that folk become experts ?

 

[colnerov]

I was looking at some footage from a private investigators Flir and all i can say is if you are having an affair with a barmaid at night down a country lane be very scared

Er, is it only barmaids? Asking for a friend.

 

[Ross365]

Consult google, then you tube

Seems to be the way these days that folk become experts ?

Mmmm.... I'm reminded of that old line that "you have to kiss a lot of frogs before you find a princess", and there are lots of frogs on Google and Youtube. Just maybe, the princess to frog ratio is better on the forum, as are the extended metaphors .

 

[The_Yellow_Ardvark]

Consult google, then you tube

Seems to be the way these days that folk become experts ?

That's hard work.
Why not cut and paste from another forum, then claim the work as your own.


Beside.

When I spent time with Everest. We had one, we could borrow, to show home owners the heat loss.
We had window and door units, we would place on the inside to show the difference.

I did notice, by playing around with the settings you could show different results.
Never sold a single door or window. But lots of a additional insulation.

 

[prepman]

I have access to a thermal imaging camera (FLIR) but I’ve never had any training in its use. Going around my house with it, I’ve spotted areas where the loft insulation needed attention, and areas where there were significant drafts, but I wonder if I could learn more from it if I had the expertise? I know that you have to take in to account factors such as emissivity and angle of imaging to make sensible readings. Can anyone suggest more skilful ways of using a camera to assess home insulation other than just looking for the blue spots?

If it can show where rats are hiding I'l buy one.

 

[voipio]

To Ross365, what is the thermal image resolution of the FLIR you have access to? Higher is better, of course.

The dedicated FLIR Tools software is worth getting. There is a very expensive paid for version, and also a freebie version that does quite a bit. Although it's primarily intended for writing reports, the image analysis features are very useful, allowing measurements like temperature average, min and max, in a user defined area, delta temps, temperature profiles and suchlike. Each thermal image generated by a FLIR camera contains a viewable visible light image in the jpg file metadata, and the temperature of each individual thermal image pixel can be read using FLIR Tools, which can be very useful for analysis after the physical survey, as it's then possible, in the thermal insulation example, to get some idea of the amount of heat lost using the u values and theory. The colour mapping can also be changed, e.g. from "Iron" to "Rainbow". It is worth keeping two copies of the thermal image files in separate directories, and only pointing FLIR Tools at one of them.

 

[Ross365]

@voipio I've never noticed it before, but this FLIR has no model id markings, other than "IR Lens f=6.8mm" - perhaps there's something in the firmware, but I couldn't find it. We bought it brand new about 10 years ago. I'll have to dig out the paperwork.

Not sure about detecting rats. It is good at finding faults in electronic kit; point it at a PCB and check out any component that is unreasonably warm or cold. It's also brilliant at finding some faults in central heating systems, and brake pads which are binding against the disks.

From what people have been saying above, it may be that I'm already using it '"adequately" if not expertly.

 

[Gareth J]

I had one for a while. Was relatively easy to get a quick visual of an area and what stands out as significantly hotter/colder than its neighboring objects, which was useful enough in most instances.

You could also get into altering settings to limit max/min visualised temps to really ignore temperatures you weren't interested in. Eg, in a room with a woodburner, if left to its own devices, as soon as the camera caught a glimpse of that, it'd adjust the scales and make everything that wasn't the woodburner "cold", loosing lots of information about, say, a neighboring window.

Another trick to find cold bridges is to let the house cool for a good while then ramp up the heating. Areas that lag behind the others are exaggerated.

 

[Migmac]

It’ll work roughly the same as mine. Air temp makes a huge difference to how they perform, below 7 degrees and they work really well. Above 8 degrees and images aren’t so good. Moisture in the air affects images too.

 

[voipio]

It is possible to see rats in complete darkness, but not if they're out of sight, although they can be seen through polythene bags (even black ones), since polythene is realtively transparent to thermal infrared. The heat from a rat's nest might also be visible from floors, walls, and ceilings, if the thermal camera is used before the heating has gone on but, bear in mind, houses are full of 24/7 heat sources: wall warts, laptop PSUs, TVs and media equipment on standby, fridges, heating controllers and (some) thermostats, cordless phones, TV antenna amplifiers.....

The FLIR Tools software is backwards compatible, as far as camera models are concerned, and works with a whole range of FLIR brand cameras. It may be easiest to pull the images off the camera via USB or SD card and copying them onto a PC before using FLIR Tools on them.

 

[dobbslc]

@voipio you seem to be well versed with these things, can you tell me if you've had any experience with Fluke thermal imaging cameras? I've been given a PTi120 for work and I'm having major problems with the Fluke Connect app. I just can't get it to work with my Samsung tablet and all the reviews I've seen for it are appalling .
I'm back in the office Monday and will give it back before I throw it in a skip!
Thanks

 

[voipio]

Not really had any experience with Fluke thermal imaging products, but did look at comparisons and reviews and pricing when trying to persuade work to buy one, and FLIR seemed to have the edge. The 120 x 90 thermal pixel resolution of the PTi120 is a bit on the low side, and the fixed focus can be quite limiting for close up imaging of small parts, and especially for making precise measurements of the temperatures of those parts. Zinc Selenide close-up lenses can be bought for not too much money, but the PTi120 doesn't make it easy to attach the lens. 320 x 240 pixel thermal images would be markedly better, at a price, though.