051

The Photographic Image as a Source of Light 
(Mnactec & IBL)

Toni Bover i Miquel Bigas.mNACTEC, Terrassa. 2009
Toni Bover i Miquel Bigas.mNACTEC, Terrassa. 2009

In The Focal Encyclopedia of Photography, Wallach reflects (1) on the evolution of the term photography throughout history. Each change in the photographic process challenges (2) what is considered photography and what is not. With the development of digital imaging and CGI, new technologies have emerged that intertwine with photography, blurring the boundaries (3) between traditional processes and facilitating the incorporation of techniques related to image management .

The hybrids between digital photography and CGI have created new photographic processes (4), such as Image-Based Lighting (IBL). This method involves photographing a scene where a virtual object will later be inserted. Based on the scene's location where the digital element will be placed, a 360º HDRI (5) panoramic image is generated. Using 3D software, this spherical panoramic image (360° x 180° equirectangular) serves as a lighting source for the CGI object. The luminance values of the HDRI photograph not only provide illumination for the virtual object but are also reflected in its shiny or specular surfaces.

While these processes were semi-manual during the first decade of the 21st century, they are now fully automated in both equipment and software.

Keywords

CGI Image management Lighting

References

Texts

  • 1. Stroebel, L; Zakia, R. (1993) Encyclopedia of Photography. Boston: Focal Press. P. 598-599.
    “The age of the word photography is a good deal more certain than the age of the idea it represents […] the word photography was derived from the Greek roots meaning to write with light, and it immediately replaced Niepce’s word, heliography (sun wrinting), and Talbot’s phrase, photogenic drawing. […] then, can we say about the systems of producing photographs that wed photochemical and electronic or digital processes, or that are purely digital?. These imaging systems are clearly, then, still doing photography and are properly referred to as photographic systems”.
  • 2. 100 IA, la nebulosa del futur / AI, the nebula of the future
  • 3. 002 La descripció de l’image management /The image management description
  • 4. Bover, A. Fotografia d’urbanisme: anàlisis de la imatge fotográfica en la comunicación visual d’un espai urbà. Regot, J. (Director). Tesi doctoral, Departament d’Expressió Gràfica Arquitectònica, UPC, 2011. P. 264-272.
  • 5. Bloch, Ch. (2007). The HDRI Handbook: High Dynamic Range Imaging for Photographers and CG Artists. Santa Barbara, CA: Rocky Nook Inc. P. 231-285.

Images

  • Bover, A. Fotografia d’urbanisme: anàlisis de la imatge fotográfica en la comunicación visual d’un espai urbà. Regot, J. (Director). Tesi doctoral, Departament d’Expressió Gràfica Arquitectònica, UPC, 2011. P. 271.
    Part of a series of images produced as teaching material for the teaching of photography and CGI. The basic photograph is the roof of the mNACTEC (National Museum of Science and Technology of Catalonia) and the virtual object was a hypothetical large specular virtual ball with the initials UPC (Polytechnic University of Catalonia). The IBL process made it possible to reflect and position the actual location of the sunlight on the virtual ball (in the daytime image) and the reflections of the artificial lighting on the specular surface of the virtual object (in the nighttime image).