The CTRatioM1/M2 ratio pyrometer provides a measuring range of 250 °C to 3000 °C at a maximum ambient temperature of 200 °C without cooling and is primarily used in metal processing applications. Furthermore, it is largely insensitive to dust, vapors or dirty viewing windows. The pyrometer even measures reliably when the optical measuring path is dampened up to 95% by dust, smoke or vapors.