hy TLM,
Good question... Normally one should consider these IR thermometers as great tools for estimating forge and kiln temperatures. The theory behind the entire story is simple (pure physics, blackbody theory): each body with a certain temperature (higher than -273°C) will emit some kind of radiation (ia infrared). Since the amount of radiation is related to this body temperature, one can use this to measure temperature. So far for the theory... In practise, each body will differ from this theoretical blacbody due to its material surface properties. The correction factor needed to solve this problem is called the emissivity of a material. This emissivity can range between 0 and 1 (steel between 0,1 and 0,9) and is needed in order to obtain a good temperature measurement. Where you can find the emissivity? You can: 1) look it up in scientific books and change the thermometer settings for the materials measured or 2) callibrate for the measuring error (by measuring the temp with your IR sensor and another reliable thermometer (so you get an idea of the error you make with the IR.
All of this might sound very complicated. Feel free to mail me whenever you want...
