What is HDRI..? HDRI stands for "High Dynamic Range Image". In short it is a specialized photographic technique that allows one to capture the exact lighting conditions and reflections on-set. By using HDRI maps in 3D software, one is able to seamlessly integrate computer generated objects into a live action environment, and thus achieve completely believable results. This is due to the fact that the correct lighting, highlights, contact shadows and reflections are contained in the HDRI photographs captured on-set during the live action shoot. The HDRI data can now be used in 3D to recreate the exact same lighting conditions that was present in the 'real world' at a specific moment in time. Realism is thus far easier to achieve in 3D, and seeing that one does not have to try and match the lighting conditions from scratch, HDRI dramatically cuts down on the lighting time in production. How does HDRI work..? The on-set lighting conditions are captured with a Fisheye lens (capable of taking 180 degree photographs). A HDRI photograph is unique in the fact that it stores both colour and intensity values of the environment, as the image integrates numerous exposures (camera stops) of the environment in one file at an extraordinary high colour depth and image resolution. This allows one to realistically control the lighting of computer generated objects in a real or 3D environment. In 'Old School' Post Production terms, the level of exposure control that HDRI offers in 3D, can be compared to the flexibility of grading 35mm film-stock in TeleCine. How can we use HDRI in Post-Production..? HDRI can be used in all the high-end 3D software packages today. Once the HDRI photographs are unwrapped and converted, it can be used in production, saving on 3D lighting and texturing time, and ensuring realistic results for film projects and high-end television commercials.