Is it better to have an IRT with a fixed or adjustable emissivity?

The default emissivity setting for all the IRT’s is 0.95. This setting will produce fairly accurate readings for the majority of items you will typically measure. Being able to set the emissivity of the IRT is useful when measuring a wide variety of materials (especially uncommon materials), or when a job requires optimal accuracy. Of course, you will need to know the emissivity of the material in order to set the IRT. A list of the emissivity of common materials is supplied for those units with the capability, but you may have to research the emissivity for uncommon materials.