Infiray and their P2 Pro - discussion

[simonesk]

Hi, and thanks for getting back to me!
I did find the SDK and tried to make sense of it, but deep reverse engineering is a bit beyond my expertise, so I wasn’t able to dive too deeply into the issue. From what I can tell, it seems that the in-app displayed temperatures are calibrated on the fly, while the exported JPGs don’t include those corrections, so they end up saving uncalibrated data.

[Sorama]

Your Set-up does not allow to measure temperature correctly.
Emission changes wrt the angle and that angle of your setup is way beyond wat is acceptable for not having emission changing too much.

[simonesk]

While I appreciate your point about angular effects potentially influencing temperature accuracy, I believe their impact in this setup is minimal. If the discrepancies between the app-displayed temperatures and those derived from the raw data were primarily due to acquisition geometry, I would expect a consistent trend, either increasing or decreasing with angle or distance. Instead, the deviations appear non-linear and do not follow any predictable pattern.

Furthermore, based on the available documentation and my understanding of the Thermal Master (Infiray) modules, the internal correction mechanisms account for emissivity and distance (to handle attenuation and atmospheric effects), but not for the angle of observation. This supports the idea that the angular offset alone is unlikely to be responsible for the inconsistencies observed.

To strengthen this analysis, I also conducted controlled tests using a temperature-regulated heating plate. The camera was mounted on a tripod at approximately 2 meters from the target to ensure stable acquisition conditions. The residuals plot (see attached) shows a deviation pattern that is better explained by calibration drift or software-side correction inconsistencies rather than geometric distortions.

[Sorama]

Among the 6 factors that influences the emissivity, are shape, angle and surface.
When the angle of measurement is greater tan 45° then emissivity is no longer static.

The impact of the angle is huge!
In this case, the angle is way more than 45° and the change of emissivity is not lineair, hence the huge error in measuring.
Use of thermography with an angle of more than 45° is not only a bad practice, it shows one does not know the huge impact onto the emissivity and therefore the measurement is truly unacceptable.

Distance by the way, is never an issue in reality because atmospheric conditions do not change unless the measurement takes place at at distance of several hundreds of meters.

While I do agree that in this setup the differences are probably due to drift or wrong corrections internally, this measurement is by default not acceptable solely because of the bad angle.
So why bother about the other issues?
 

[Sorama]

@simonesk

do you have a normal picture of the plate you're heating?

Wat is the surface, what are the dimensions of it?

[simonesk]

@Sorama Thanks for the interesting observations and thoughtful points, vey much appreciated!

You're absolutely right that the angle of measurement can have a significant influence at extreme geometries. While I currently believe that, in this particular setup, the impact of emissivity due to viewing angle might still be minor compared to other sources of error (such as calibration drift), I’m completely open to verifying whether that assumption holds.

That said, it's important to note that my testing isn’t intended to assess the accuracy of true kinetic temperature readings. Rather, the goal is to understand why discrepancies arise between the thermal data shown in the app and the raw data retrieved from the system.

I'll be away for a few weeks, but I do plan to revisit and replicate the experiment once I’m back. It should give a better indication of whether the viewing angle contributes significantly to the observed offsets. I’ll keep you posted on any developments.

As for your question regarding the surface and dimensions: I’m not currently in the lab, so I can’t provide precise details at the moment. Roughly, though, it’s a 20 cm rounded heated plate with a dark-colored heating base. I’ll share more specifics once I’m able to rerun the test.

[ir-30thz]

I am a little confused about the status of the Redux software. Is the version on GitHub version 0.92 or 0.93? I ask because I am interested in the range of colour palettes which are quoted for v 0.93 but the version I downloaded does not seem to have all of them.

[MrCreosote]

I'm 72 and have been putting off a thermal camera purchase long enough.

It seems all roads lead to the P2 Pro - the 16 pages for this camera in this sub forum, only topped by >50 for FLIR strongly indicate this is the most popular camera on the market.  (My Bad:  there are too many pages to read, so I'm posting this being a lazy slob - yet, it is 2025 and things do change quickly nowadays.)

My intended usage and the trifecta:  PCB  repair, home inspection and looking for rabbits and deer eating my plants.

QUESTION:  I assume it will do all of this better than anything at this price level?
QUESTION:  The Macro Lens is pricey, are there generic cheaper available?
QUESTION:  While it seems that this resolution is necessary for PCB repair, still, must ask are there any other cameras that would that would be a better value (cheaper OR more money for lots more capability? - expected answer No)
QUESTION:  Any reason to get a dedicated hand held unit?  What would be the equivalent candidate?  Uni T 260?

Thanks in advance
Tom

[MrCreosote]

Looking like Tooltop T7 and Topdon TC001 are cheaper alternatives + DIY generic macro lens.

[toske666]

Hi everyone,

I recently damaged the protective lens cover on my Infiray P2 Pro thermal camera. The original lens was very thin (less than 1 mm thick), about 12 mm in diameter, and had a slight golden or mirror-like appearance. When I removed it, the camera worked fine, but when I replaced it with a regular glass lens, the camera couldn’t see anything.

Could anyone please confirm what material the original protective lens is made of? Is it Zinc Selenide (ZnSe), Germanium (Ge), or something else? Also, if you know the typical thickness and optical properties of that lens, that would be very helpful.

Thanks in advance for your help!

[toske666]

I've also attached a few photos of the original broken lens, so you can take a look and share your opinion.

[Fraser]

The lens protection window is made from Chalcogenide IR transmissive glass, as is the cameras actual lens. Sometimes Silicon is used but that has poorer transmission characteristics at LWIR wavelengths so must be kept very thin.

Ordinary glass is opaque to the LWIR spectrum, as you have discovered. The cameras measurement system will have been calibrated to take account of the small transmission loss introduced by the thin window but the error introduced by the absence of the window will be very small. The Thermal Master P2 does not have the window and you can operate your P2 Pro without it if you want. If you desire the protection afforded by the window on the P2 Pro, you will need to find a ZnSe, Germanium or Chalcogenide IR glass (GASIR) window of the same diameter, similar thickness to the original, and it must be AR coated for LWIR use. Infiray and Thermal Master do not offer the window as a spare part that you can purchase. A thick window will introduce slightly more transmission loss and may interfere with the correct fitting of the close-up lens.

Hope this helps

Fraser

[Fraser]

I just searched for a suitable replacement window for your P2 Pro and they are hard to find. Whilst I could find a “Polished”, uncoated window of the correct dimensions, I could not find an AR coated window. Do not be tempted to use a window that is not AR coated for LWIR, it will perform poorly and ruin your cameras measurement accuracy.

In your position, I would likely use the camera without the window, as with the TM P2. A custom made LWIR window will likely be uneconomic. Warning, if you find a ZnSe window with the idea of cutting it down to the correct diameter, do not do so. ZnSe is harmful if cut or ground.

Fraser

[camellos]

Excellent kit - I got the P2. I've been more than happy with it. Much better than the old crappy flir I had before (and without teh dreaded dead battery lock-out problem!)

[Maniaxx]

Does it support "fixed temperature range"?
Some ppl on amzn claim it does not. That would be a showstopper.

Is the P2 fading out? I just see P2Pro on amzn.

[Leon W]

Hi Fraser, could you provide me with an SDK for development?

[Fraser]

I will look in my archive to see if I have an SDK for the Infiray P2.

Fraser

[Fraser]

Leon W,

As requested, the Official Infiray SDK for the P2 Pro. This is for Android.

https://drive.google.com/file/d/1VKbWElMLlL-_GlgFc1v_tTk3uf451DqG/view?usp=sharing

Other Infiray SDK's were provided for the Tiny1-C and these also work with the P2 Pro as it is basically a Tiny1-C core in a metal case. Those SDK's covered several Infiray ASIC's and supported Windows and Linux. That multi ASIC SDK set was not on general release to the public, but I do have it.

Fraser

[LEECH666]

Hi guys, long time no see.

I have a problem. My "P2 Pro" only goes to 177°C or thereabout. Reading the initial post it looks like I've might have gotten a normal P2 which has a temp limit around 170°C. So I kinda feel scammed now from the official Infiray Store on Amazon.de because I definitely ordered and payed for a P2 Pro.

Is there a definitive way to tell apart if I have received a P2 Pro or a normal P2?

Nevermind! I am too silly.

There is this white, semi translucent hovering white circle that brings up another menu. I didn't see this menu before. But if I set the mode to wide range or auto it goes higher than 170° indeed. Issue resolved.

Update:
While my P2 Pro now measures beyond 170°C it seems to be super inaccurate for example when I want to check the 360°C set on my soldering iron it reads like 250°C or way too low. Has anyone here an idea what could be the reason for that?

[Fraser]

Have you used an appropriate Emissivity figure to match the soldering iron surface finish ? If it is glossy or bright you will have to set a lower Emissivity figure.

Fraser

[breyt]

For me, the apps from the play store work on an old Pixel 2, but none of those I tried worked on my new Pixel 9 Pro with Android 16.

Due to that I have started building a new Android app for the Infiray P2 Pro - and if possible other similar USB thermal cameras.

It's in a working condition, and I'll release it as open source when I ironed out some parts. The app is based on libuvc/libusb, the APK is just 7.6MB, doesn't have any other permissions than for the USB and camera

Let me know if you are interested in testing!

[santelelle]

@breyt

Please add the option to fix the temperature scale (e.g. colormap going from 15 to 80C regardless of the range of visible value). Everything beyond should be clamped. All the apps out there lack this essential feature.

Would be really interested in testing the app!

Keep the good work!

[breyt]

Thanks Santelelle! In principle the locking functionality is already there, it can be enabled in the three dots menu. I also really wanted to have it. It fixes the color scale - let me know if that's what you were looking for, too.

I attached the APK if you want to test it. I'd be happy about feedback! Sometimes it happens you have to force-close the app and restart when re-attaching the camera or re-opening the app, let me know if it happens for you. Will try to iron that out.

I'll make the project public somewhere soon.

[santelelle]

Thank you breyt! Unfortunately I did not manage to install the app. I get "package appears to be invalid". I am on a Samsung S22 Ultra.

[breyt]

Can you try again with the attached one? I shared the APK that Android Studio created, which was built only for my target device API.