Limits of HDR Scene Capture
John J. McCann, Alessandro Rizzi · 2011
High-dynamic-range images are superior to conventional images. The range of light falling on the sensors is limited by veiling glare from parasitic images in glass lenses and diffracted fog in pinhole images. This chapter describes measurements of how much veiling glare limits HDR imaging in image capture. Glare is the scene- and camera-dependent scattered light falling on image sensors. Glare limits the range of luminances that can be measured accurately by a camera, despite multiple exposure techniques. The authors used 4.3 log unit dynamic range test targets and a variety of digital and film cameras. In each case, the camera response to constant luminances varied considerably with changes in the surrounding pixels. They unable to make accurate camera estimates of scene luminance for the scenes studied here using HDR multiple exposure image capture. The ranges measured here are scene dependent, and cannot be used to make conclusions about other scenes. Controlled Vocabulary Terms light scattering; photographic applications