Color temperature in digital photography and the blackbody spectrum

摘要

As an application of the blackbody spectrum outside of pure physics, we present how the phenomenon applies to digital photography. While shooting the AAPT Films series, the authors often would discuss how the names of "warm" and "cool" light sources strikingly mismatch their temperature values. Indeed, the so-called "cool tones" are over 7000 K, while the "warm tones" are at a much lower 3000 K. In this article, we discuss a few demonstrations of blackbody radiation and explain how the concept applies to photography and astronomy, and even dare to utilize the camera's white balance feature as a thermometer.