Are infrared sensors inaccurate at higher temperatures?

There is a process for calibrating thermal measuring instruments at higher temperatures.

There is a process for calibrating thermal measuring instruments at higher temperatures. The way we would confirm that the measuring instrument was reading correctly, would be to have an instrumented specimen with a thermocouple and then site the thermocouple location with the infrared measuring device. Then adjust the emissivity of the infrared measuring device to match the thermocouple temperature. Once you do that you know that the temperature of the metal part is accurate, and you’ll be able to use it in your manufacturing process.