Validation of High Dynamic Range Photography as a Tool to Accurately Represent Low-Illumination Scenes 2012-01-0078

Previous research [1] described a procedure for creating prints from digital photographs that accurately represent critical features of visual scenes at low levels of illumination. In this procedure, observers adjust the brightness of a digital photographs captured using standard photography until it best matches the visible characteristics of the actual scene. However, standard digital photography cannot capture the full dynamic range of a scene's luminous intensities in many low-illumination settings. High dynamic range (HDR) photography has the potential to more accurately represent a viewer's perception under low illumination. Such a capability can be critical to representing nighttime roadway scenes, where HDR photography can enable the creation of more accurate photographic representations of bright visual stimuli (e.g., vehicle headlamps, street lighting) while also maintaining the integrity of the photograph's darker portions. Using a photographed real-world, low-illumination scene, brightness adjustments and subjective ratings of the visibility of multiple objects were collected from naïve observers using the updated method with both standard and HDR photographs. A comparison of observers' ratings of the gamma-corrected photographs to the actual scene indicates that the HDR photograph represents a majority of the objects in the scene with greater fidelity than does the standard photograph. These findings support the validity of the updated method, using HDR photography, to produce accurate depictions of low-illumination scenes.