Probing Planck's law at home

We report on the physics around an incandescent lamp. Using a consumer-grade digital camera, we combine electrical and optical measurements to explore Planck's law of black-body radiation. This simple teaching experiment is successfully used to measure both Stefan's and Planck's constants. Our measurements lead to a strikingly accurate value for Planck's constant: h = 6.7 +/- 0.4 x 10(-34) kg m(2) s(-1). A digital camera is thus sufficiently good equipment to measure a constant directly related to quantum mechanics. The simplicity of the proposed experiments makes this paper appropriate for undergraduate students interested in the experimental aspects of fundamental physics.