I have the Fluke TIR1 with the 160X120 sensor. I understand that there will not be high resolution from that sensor and that is not necessary for my work. (The camera performs excellent for building diagnostics.)

BUT, I keep wondering about when I upgrade, what will the diffrerence be in sensors. Do I really need to go as high as 640X480?

Does anyone have thermograms of the exact same object taken with the three available sensors, 160X120, 320X240 and 640X 480? I know that I would love to see the comparison, especially considering we are always thinking along the upgrade line.

Something that will show the differences such as a building skyline or a building from a distance?

 Thanks in advance.

 

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Darrell Paul
Wood Frame Construction Specialist
Level I Thermographer
403-586-1950
www.qstat.ca

Good morning Darrell.  Greetings from Ottawa.

I have a Ti25 and have been asking the same questions.  I think John Snell has a post on this forum comparing sensor and sensitivity options, along with comparative (not identical, but illustrative nonetheless) shots.

In my case, I did a side by side comparision, with the assistance of a Level III Thermographer, between my Ti25, 160 x120, 0.1 NETD and a Ti55FT, 320x240, 0.05 NETD, using several different types of materials, (including brushed aluminum, a block of phenolic, wrought iron and wood) and a thermos holding an ice cube and water bath.  All had stablised in a freezer and were placed in an open indoor area with no known sources of background temp anomolies. The cameras were held as closely as possble to the same distance and viewing angle.  I then looked at the images side by side in Smartview and again in a post processing graph.

Here's where the solution takes on elements of both art and science.  The relative advantages of the Ti55FT depend on the application.  In my case, where most of the work requires the best possible resolution around and just below 0 deg C, I focussed my attention on how visible the ice cubes were in the near-freezing water of the bath.  While the Ti55 produced clearly superior results at the warmer temperatures, especially on the metals, I didn't see enough of a difference around zero to justify the upgrade.  Additionally, data export in Smartview is limited to one decimal place for all models, so the higher accuracy of the Ti55 didn't translate into post processing for me. 

Would the Ti55 outperform at typical house temperatures?  Without a doubt it could, but again I'd stress that it depends on how you are using it.  I am still evaluating the upgrade path for several larger detector platforms, because the one advantage I increasingly need is the additional resolution at range that the bigger detector gives me.  In this market though, the combination of rapidly evolving technology and shaky industry financials has me waiting before I lock in a choice. 

I hope this helps, others with more expertise will surely have better advice.

All the best

-John

Hi Darrell,

These series of images may help you better understand the differences seen in array size.  As you'll see, at the distances in these particular shots, there's not much of a difference.  Certainly we can see enough detail in each to conduct the job. 

In the first set we're looking at the same corner of a residential home with three different thermal imagers with three different array sizes.  The second set is in an outdoor substation using two different array sizes. 

In my own personal opinion, for residential home inspections, it's very difficult to justify upgrading to a 640x480 system. I would argue you're better off with a smaller array size that has a greater thermal sensitivity (70 mk or better, i.e. lower number).  This will give you the ability to work in more marginal conditions as well as detect small, subtle differences, in surface temperature that a 100 mk, or larger, system might possibly miss.

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Matt Schwoegler
The Snell Group

Our Knowledge. Your Advantage.

Thanks you guys for that feedback. I have been really happy with my TIR1 which is .07MK with the 160X120. I wanted to get some ideas as to how much better a 320X240 with the same .07MK would resolve.

So basically if I understand this correctly, with the same NETD I just have to get closer to acheive the same result? The resolution simply would allow the scanning to occur from a greater distance.

 

Thanks again

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Darrell Paul
Wood Frame Construction Specialist
Level I Thermographer
403-586-1950
www.qstat.ca

In general this is true. Image processing is a "black art" so it may vary from model to model. Your 160 system can "become" a 320 system by either moving half again as close to the subject or by putting on a 2X telephoto! The difference will be your field of view (the overall image size you see) will be smaller. So, if you were looking at a house, you'd see a quarter of the house rather than the whole thing. You can use this trick to take multiple images with the 160 array and merge them together to gain improved spatial resolution.

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Thermally Yours,

John
ASNT NDT Level III #48166
The Snell Group
www.thesnellgroup.com
www.thermalsolutions.org
800-636-9820

Would digital zoom have the same effect as moving closer or does that internally magnify the image? Like zooming in on an already poor picture if you know what I mean.

 

Thx

Digital zoom does NOT improve resolution at all. You just get magnification of the existing image.

 

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Thermally Yours,

John
ASNT NDT Level III #48166
The Snell Group
www.thesnellgroup.com
www.thermalsolutions.org
800-636-9820