High dynamic range (HDR) imaging has become a powerful tool in computer graphics, and is being applied to scenarios like simulation of different film responses, motion blur, and image-based illumination. The HDR images for these applications are typically generated by combining the information from multiple photographs taken at different exposure settings. Unfortunately, the color calibration of these images has so far been limited to very simplistic approaches such as a simple white balance algorithm. More sophisticated methods used for device-independent color representations are not easily applicable because they inherently assume a limited dynamic range. In this paper, we introduce a novel approach for constructing HDR images directly from low dynamic range images that were calibrated using an ICC input profile.