Ben321 wrote:
Radiometric (temperature measurement via LWIR detection) capability probably maxes out at 100degC (212degF), just like with the FLIR One. However its ability to see LWIR radiation probably goes well above that.
Hotter things simply give off more LWIR, not some different sort of LWIR. See Wikipedia on Planck curves and Black Bodies. The problem is sensor saturation.
While a radiometric app that displays temperature probably will artificially limit the range by indicating that it maxed out at 100degC, a 3rd party app that can access the raw pixel data from the sensor probably would be able to detect LWIR radiation from much hotter sources, even if it couldn't accurately assign a temperature to it, as the per-camera calibration values needed to calculate this are probably proprietary, and the only app that will have access to these values will be the official one, which will NOT allow direct access to the raw data by the end user, just like with the FLIR One SDK sample app.
Unlikely. To get a good noise free image the scene dynamic range will be quite limited. A large dynamic range setting would push the NeTD/MDTD up to 500mK or more. There is nothing proprietary about the calibration, just whether the manufacturer can be bothered plotting the curve all the way. Thermal sensors are linear in energy, so it is just maths to convert that scale to temperature.
However, once temperature is above about 1000degF, then sensor's output may overload the ADC (analog to digital converter) causing it to wrap around back to digital output of 0, as I found it does on the FLIR One when accessing the raw 14bitsperpixel data through the FLIR One SDK sample app
Well before that I expect, more like 150°C as I suggest above. Higher temperature ranges need special low gain modes in the sensor to avoid saturation. These may have their own factory calibrations or might be simply mathematical relations (like 1/8th gain and sort out offsets with a shutter calibration).
What you saw on the FLIR is either a palette that is black = overload or else simply bad coding. It is not the the ADC, an ADC will sit at 16383 when overloaded but when the gain/offset corrections are applied to 16383 that may wrap back if the code is not written with very hot things in mind. Some of the FLIR Twitter images of the K2 fire camera at the FDIC show the black-very hot artefact too, with a flame measured at >120°C.