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Image Gallery

Please calibrate your monitor to be able to see 11 distinct shades of grey in this strip.

Photographs of the Atrium

The following page illustrates the problems that might arise during comparison of the rendered images against the corresponding photographs of real-world environments.

All presented photographs were taken in the same lighting conditions. The atrium is a very challenging environment to take photographs at the night time because of mixed fluorescent and incandescent lighting. The results obtained using the
standard photographic techniques were not satisfactory.

Picture taken using a Nikon F4 camera with lens Nikkor 28mm.
Film FUJICHROME  daylight ISO 400 was used. Almost the same results were obtained using a standard Fujicolor film. 

Colors are washed and the overall photograph tone is too yellowish; lights in the corridor are really out of gamut. Shadows and highlights are too pronounced.

Picture taken using a Nikon F4 camera with lens Nikkor 28mm.
Film FUJICHROME Tungsten ISO 64/19 was used.

The picture looks somewhat better than the one taken with the standard film, but it is blueish and even greenish in the corridor because of the halogen lighting. Highlights are too pronounced.

Picture taken using a Minolta RD-175 digital camera with lens 60mm.
The pictures of the upper and lower atrium parts were taken in 2 steps and then assembled.

Although colors lack in contrast, the digital photograph tone is closer to reality than for pictures taken using the standard photographic techniques. 

Rendering of the Atrium

All images presented below were rendered using the Density Estimation Particle Tracing (DEPT) global illumination technique described in the reference [1]. The technique was implemented as a part of the Inspirer system (Integra, Inc.).

"Artistic" approach with manual tuning of surface reflectances and colors


Physically-based lighting simulation using the measured BRDF values


Physically-based lighting simulation using the averaged specular and diffuse reflectances
(We refer to this approach KdKs)


Direct lighting only

Panoramic view of the Atrium

Panoramic image created by Edward Kopylov.There is also an interactive panorama based on the image above.
Note: It works only with Microsoft Internet Explorer.

[1] Density Estimation Particle Tracing (DEPT):
V.Volevich,K.Myszkowski, A.Khodulev, and Kopylov E.A. Using the Visible Differences Predictor to improve performance in progressive global illuminaton computations. ACM Transactions on Graphics, Vol. 19, No. 2, pp. 122-161, 2000.

Model | Material | Luminaires | Illumination
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