Image-Based Lighting IIReal objects under new lightingRendering Light Probes as Light SourcesSlide 4A Lighting Reproduction ApproachComposited ResultsLight Stage 1.0The Light Stage: 60-second exposureSlide 9Modulated ImagesLight Stage 1 ResultsLight Stage 3Structured LightLight Stage 6Environment Map from Single Image?Eye as Light Probe! (Nayar et al)Cornea is an ellipsoidEllipsoid fittingSlide 19Putting it all together!Reach for the skyDirect HDR Capture of the Sun and SkyExtreme HDR Image SeriesSlide 24Spectral Calibration – ND filters are NOT Necessarily Neutral!Two Complete days of HDR Lighting (see video)Lit by sun and sky9 samples per pixel, 17 min.16 samples per pixel, 46 min.100 samples per pixel, 189 min.A sunlit sample pointSlide 32Slide 33Slide 34Slide 35Slide 36Slide 37A shadowed sample pointSlide 39Slide 40Slide 41Slide 42Slide 43Slide 44HDRI Sky ProbeClipped Sky + Sun SourceLit by sky only, 17 min.Lit by sun only, 21 min.Lit by sun and sky, 25 min.Slide 50Slide 51Slide 52Slide 53Image-Based Lighting II15-463: Computational PhotographyAlexei Efros, CMU, Fall 2008…with a lot of slides donated by Paul Debevec© Clément PolineReal objects under new lightingRendering Light Probes as Light Sources19991999A Lighting Reproduction ApproachComposited ResultsLight Stage 1.0Debevec, Hawkins, Tchou, Duiker, Sarokin, and Sagar. Acquiring the Reflectance Field of a Human Face. SIGGRAPH 2000.Debevec, Hawkins, Tchou, Duiker, Sarokin, and Sagar. Acquiring the Reflectance Field of a Human Face. SIGGRAPH 2000.The Light Stage:60-second exposureLight Stage – 4D Reflectance FieldLight Stage – 4D Reflectance FieldModulated ImagesLight Stage 1 ResultsEnvironments from the Light Probe Image Gallerywww.debevec.orgEnvironments from the Light Probe Image Gallerywww.debevec.orgLight Stage 3Structured LightLight Stage 6Environment Map from Single Image?Eye as Light Probe! (Nayar et al)Cornea is an ellipsoidEllipsoid fittingPutting it all together!Reach for the sky•How can we capture the whole sky as an environment map?•What happens with the sun?Direct HDR Capture of the Sun and SkyDirect HDR Capture of the Sun and Sky•Use Sigma 8mm fisheye lens and Canon EOS 1Ds to cover entire sky•Use 3.0 ND filter on lens back to cover full range of light–Only 0.1% of light gets through!•Use Sigma 8mm fisheye lens and Canon EOS 1Ds to cover entire sky•Use 3.0 ND filter on lens back to cover full range of light–Only 0.1% of light gets through!Stumpfel, Jones, Wenger, Tchou, Hawkins, and Debevec. “Direct HDR Capture of the Sun and Sky”. To appear in Afrigraph 2004.Stumpfel, Jones, Wenger, Tchou, Hawkins, and Debevec. “Direct HDR Capture of the Sun and Sky”. To appear in Afrigraph 2004.Extreme HDR Image SeriesExtreme HDR Image Series1 secf/41 secf/41/4 secf/41/4 secf/41/30 secf/41/30 secf/41/8000 sec f/161/8000 sec f/161/30 secf/161/30 secf/161/250 secf/161/250 secf/161/1000 secf/161/1000 secf/161 secf/41 secf/41/4 secf/41/4 secf/41/30 secf/41/30 secf/41/8000 sec f/16only image that does not saturate!1/8000 sec f/16only image that does not saturate!1/30 secf/161/30 secf/161/250 secf/161/250 secf/161/1000 secf/161/1000 secf/16Extreme HDR Image Series- sun closeupExtreme HDR Image Series- sun closeupSpectral Calibration – ND filters are NOT Necessarily Neutral!Spectral Calibration – ND filters are NOT Necessarily Neutral!Before correctionBefore correctionAfter correction based on MacBeth ColorChecker chart appearanceAfter correction based on MacBeth ColorChecker chart appearanceTwo Complete days of HDR Lighting(see video)Two Complete days of HDR Lighting(see video)Feb 22, 2004 Feb 23, 2004(day averages at 1 min. intervals)Lit by sun and skyLit by sun and sky9 samples per pixel, 17 min.9 samples per pixel, 17 min.16 samples per pixel, 46 min.16 samples per pixel, 46 min.100 samples per pixel, 189 min.100 samples per pixel, 189 min.A sunlit sample pointA sunlit sample pointA shadowed sample pointA shadowed sample pointHDRI Sky ProbeHDRI Sky ProbeClipped Sky + Sun SourceClipped Sky + Sun SourceLit by sky only, 17 min.Lit by sky only, 17 min.Lit by sun only, 21 min.Lit by sun only, 21 min.Lit by sun and sky, 25 min.Lit by sun and sky, 25 min.24 Samples per Pixel – 6h, 22min24 Samples per Pixel – 6h,
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