The surface of various materials can have a huge impact on how your infrared camera sees energy. The same material can look very different, if the surface varies in smoothness or roughness. Plus, some materials have different degrees of reflection vs emissivity.
Color can have an affect on how the block absorbs the sun’s radiation, which
can make blocks warmer or cooler. Infrared radiation is not affected by color.
Different frequencies.
If you heat a multi-colored block with a heat source under it, the color will not matter. Your IR camera will see the same image on each color. (if all the colors are the same texture and materials).
If you allow the block to absorb ultraviolet sun light, the darker colors will absorb more energy, because colors matter when dealing with ultraviolet frequencies.
Texture can cause a difference as well. If you apply color with more, or less texture, then you change things in the IR spectrum in how your IR camera sees it … and the ultraviolet spectrum as well.
