Originally Posted by perryg114
Non-contact IR thermometers (pyrometers) are not accurate for measureing temperatures because most of them assume the emmisivity is something like .9 which is not the case in most circumstances. The best way to measure temperatures is with a thermocouple glued to or imbedded in the surface. An IR thermometer is going to give you two different temperatures on two different materials at the same temperature. IR thermometers are good for looking for hot spots or cold spots in a given material. They have crappy absolute accuracy unless you can tell it what the emissivity is for your material. Black would have an emmisivity of 1 and gold has an emmisivity of .1.
I love this forum. Anywhere else and the conversation would have degraded into "No, this is better because I said so." Instead, we have an intelligent, well-articulated, and interesting conversation occurring. Go figure.
Anyway, I would like to just add my support of the thermocouple comment. That was my first impression when I read the IR thermometer portion. Even the $80k IR video cameras with extremely high sensitivity that we buy from FLIR are nothing compared to thermocouples actually sitting in the process or on the metal skin (hydrocarbon processing background).