Black Body Thermal References and Fraser's new Black Body project :)

[eKretz]

Fraser, I have a question for you. When a thermal cam is calibrated, does the entire field of view need to be filled by the radiating surface?

[bap2703]

If you want the entire field of view properly calibrated, yes !
If really desperate you can probably radiometrycally calibrate only part of the sensor and extrapolate to the uncalibrated area. That should work provided that you do that on top of an existing non uniformity correction.

[eKretz]

Interesting. I'm just wondering how they go about this with something like the Flir EXX series. As I recall, the photos posted from their cal lab seemed to show black body radiators only around 4" diameter. That shouldn't fill the field of view at minimum focus distance. I was under the impression that they were calibrating the cameras with these, but perhaps they were only testing calibration?

[Fraser]

The pictures I posted are of a calibration test jig and not the factory camera calibration process. It tests accuracy and uses the centre pixels onl to measure the thermal references. They do not create the NUC tables with that jug. At the factory the cameras are two point calibrated, or more points if needed. They are positioned with their lens inside an aperture that contains a black body emitter. The emitter fills the FOV.

Fraser

[eKretz]

So does the camera need to be focused on the radiator or does that not matter?  Can it be closer than minimum focus distance if it fills the field of view? I was under the impression that the camera needed to be focused for an accurate temperature reading.

[bap2703]

As I recall, the photos posted from their cal lab seemed to show black body radiators only around 4" diameter. That shouldn't fill the field of view at minimum focus distance.

The key here is that there is no need to focus. Since you are looking at a supposedly uniform target adding any blur should'nt change anything to what you are seeing.
Hence a calibrator large enough to fill the field of view can be at any distance... So probably quite close and quite small.

I hope master Fraser agrees with that theory

Errata, beware of your optics, if it has a large range of focusing depth or even a zoom.

[eKretz]

Gotcha. Thanks for the info.

[Devov]

Let me know if you guys need any help determining thermal stability of the paints you're using.  I have a PerkinElmer TGA in our lab and I'd be happy to run some samples.

[Bill W]

The key here is that there is no need to focus. Since you are looking at a supposedly uniform target adding any blur should'nt change anything to what you are seeing.
Hence a calibrator large enough to fill the field of view can be at any distance... So probably quite close and quite small.

Correct

Bill

[ksilabs]

On black bodies -- does anybody know anything about those cheap Electro Optical B1804D and B1804D/S7 sources that are on Ebay now? What are the temperature ranges and other parameters? I don't mind making my own controllers for those but there is ABSOLUTELY NO information on them at all so I don't even know if they are worth buying even that cheap...

Electro Optical site only shows new ones, no information on anything older at all like they never existed. I don't even mention manuals; there are no even rudimentary datasheets anywhere...

I bought a cheap WS152 source just to look what it is and it turned out to be a cavity unit i.e. a high-temp one but what is its temperature range? Having it in my hands didn't make this matter any clearer

I do have a very nice IR-160 wide area (12"x12") 350 degree Celsius source from Infrared Systems Development as well as their hi-temp cavity one, IR-563 that goes up to 1050 degrees Celsius but only have one IR-301 controller and one cable for both and no manuals but those are current production units so there is at least some information on the manufacturer's website and I'll try to fish manuals and other info from them in a week or two when all other urgent tasks are done.

But there is absolutely nothing on those Electro Optical units -- zero, nada, zilch...

BTW, Flir asks $625 for Exx calibration PER LENS so it is just mere $1,875 for 3-lens calibration And they recommend to spend that pocket change on calibration each and every year...

With just IR-160/301 I can do such calibration even every week for free and I spent on those less that just one Flir factory calibration. I would like to extend my calibration capabilities into negative temperature range using some older source as a base for Peltier cooled/heated one but it would be very nice to have at least some information to find out which source to buy if at all...

[eKretz]

Are you already doing calibrations on your Exx? I and I'm sure others here would be very interested in finding out the workflow/procedure. A how-to thread would be welcome. I have done a little poking around in the service menu but don't have a black body yet, so haven't got that far into it.

[Bill W]

Those are around the 1990 era, EOI have been sold since then and certainly dropped factory support.  However a few ex-EOI local service centres might be able to help, but even there as people retire the knowledge is going with them.

Also there were generally differential target units for MDTD / MRTD rather than a flat field calibrator.

regards
Bill

[ksilabs]

I've just got my blackbodies, not setup/tested them yet. Sure I will share the entire procedure but you guys should be aware that I have a REAL extended surface blackbody, IR-160, that is specifically designed for such calibration and has 1 square foot (12" x 12") uniform radiating surface. It is really big and fills the entire FOV as it is supposed to.

Please let me 2 to 3 weeks to post a report -- there are too many more urgent task now.

Then, my camera is 64xxxxx E40 with 3.18.0 firmware so it is missing the entire service menu as well as some files from E60. I'm going to try parts from 49xxxxx firmware this weekend but not sure it will work fully although it might if done properly. Various missing E60 parts would be nice to have but not all that critical.

The highly desirable part is that 3.12.7 firmware update that's been mentioned several times and somebody even told he found it on his PC and it had all the service menu parts. It would've been absolutely best thing to have if it really does have those parts.

64xxxx E60 files would've been also nice if somebody cared to share those...

[eKretz]

Even if I don't end up being able to do it, I would still be interested in learning the procedure. And I have a set of config files for E60 but only the 49xxxxx version, don't have the 64xxxxx one.

[ksilabs]

Ah, config files are of no interest, most of the FULL configuration is already there It is used when camera is switched into service mode -- full resolution, no noise and other things... It's switched back to the original crippled configuration when it is out of service mode but nobody forbids reading that service mode config and edit your working one accordingly...

Reading strings from 2.27.16 prodapp.exe now (strings prodapp.exe | less) -- quite a fascinating reading indeed

Next step is reworking web server files to match 64xxxx Exx configuration and attempt to get a fully working service menu on my E40 with 3.18.0 firmware. But that will probably come tomorrow.

[ksilabs]

OK, it looks like prodapp.exe binary from any 64xxxx camera is required. The one I got from 2.27.16 won't start on my 3.18.0 64xxxxx camera. No error messages, just won't start.

Other binaries (e.g. i2c.exe, fvd.exe) from 2.27.26 run just fine.

It might be due to hardware type -- gethwtype.exe from 2.27.16 returns F1 while original 3.18.0 one returns F2.

[mahony]

There is a very nice description how to calibrate TEC-less and shutterless uncooled microbolometer cameras:
https://www.j-sens-sens-syst.net/5/9/2016/jsss-5-9-2016.pdf

The procedure is pretty straight forward but requires 2 blackbody sources and one climate chamber for the camera...
2 BBs - checked
camera with different lenses - checked
climate chamber - tbd

;-)

[ksilabs]

There is a very nice description how to calibrate TEC-less and shutterless uncooled microbolometer cameras:
https://www.j-sens-sens-syst.net/5/9/2016/jsss-5-9-2016.pdf

The procedure is pretty straight forward but requires 2 blackbody sources and one climate chamber for the camera...
2 BBs - checked
camera with different lenses - checked
climate chamber - tbd

;-)

There is a calibration routine in prodapp.exe so it makes life much easier. The only requirements is to get that prodapp.exe run on newer Exx F2 cameras with 3.xx.x/4.xx.x firmware

Climate chamber is nice but not absolutely required -- it is possible to do this without it. The more blackbodies the better

[ksilabs]

No luck getting 3.12.7 or so firmware or at least prodapp.exe binary from anything 3.xx.x earlier than 3.18.0. I would even pay a reasonable price for that if somebody doesn't want to give it up for free.