EMISSIVITY COEFFICIENTS OF COMMON R/C MATERIALS Surface Material Emissivity Coefficient Aluminum Anodized 0.77 Plastics 0.91 Rubber, Hard Glossy Plate 0.94 Carbon Pressed Filled Surface 0.98 In general, if you are not comfortable changing the emissivity value, it is best NOT to change it. The default emissivity value is 0.95, which will provide accurate temperature measurements for most materials.