LightLab - Where Environment meets Design

An Introduction to HDR and the LightLab Project is available in PDF format.

This project aims to integrate the teaching of environment and design in architecture studio, via the medium of light, to achieve three main objectives:

• Enhance architecture students' understanding of the scientific, technical and visual qualities of a core component of their discipline: light
• Promote a streamlined and customised workflow for the integration of technical information into studio to stimulate genuinely environmental design
• Create common ground for better communication and understanding between design and technical staff

Specifically this project aims to take advantage of new physical and computational techniques to bring the technical and aesthetic qualities of light together in architecture studio. Students will be able to work with the exact lighting conditions from exterior and interior scenes of their choosing, and develop an appreciation of the lighting qualities of existing spaces and the potential of new ones.  The project bridges the teaching of technology and design, and students receive a more holistic education as a result. In turn, a teaching approach better able to meld these two elements is much more likely to produce built environment professionals capable of producing the sustainable but desirable buildings we require in the future.

One way to teach environment with design is to bring them closer together through the use of a medium that has aspects of both. Light is the perfect medium for this context as its behaviour can be described mathematically, its characteristics are environment- specific and it has obvious implications for the visual quality of space. In this project High Dynamic Range (HDR) imaging is a means of bridging technology-centred and design-centred teaching.

HDR is an image format like j-peg or gif. Images are created by compositing a number of conventional digital photographs with different exposure levels of the desired interior or exterior location. This compositing creates a new digital image that contains data about the brightness of each pixel. Importantly, this data can represent the full brightness spectrum seen in the natural environment, from direct sunshine to the darkest shadow, thus overcoming the narrow brightness range of conventional digital images and making the resultant image physically accurate. It is this feature that gives them the name ‘High Dynamic Range’. If an HDR image is generated at the site of a potential architectural intervention, for example, then the exact characteristics of the lighting environment, such as the influence of surrounding structures, sky conditions and time of day, can be captured.

As HDR images contain accurate brightness information, they can be used in software packages to provide realistic lighting environments for 3D computer models, which in turn can produce more subtle visual output or accurate numerical lighting data for analysis. Once this lighting data is embedded within the computer design environment, the influence of form or material on light quality can be easily assessed, from either a qualitative or quantitative point of view, and in this way critical environmental analysis is effectively conjoined with design practice. As a result, students gain a direct link between the physicality of their proposed site, the visual quality of their work and an appropriate design response to both. Moreover, design and technical staff also gain a mechanism for better communication and understanding, fostering broader and closer co-operation in the future.

For this qualitative analysis, next-generation rendering software (that creates a 2D image from a 3D model) called LuxRender will be used. LuxRender offers not only accurate results, but an ease of use that makes this software highly suitable for architectural education purposes. The accuracy of the visual results is vital if students wish to know and manipulate the actual and subtle visual quality of the spaces they create. For example, if novel light redirection structures are employed, then the student designer needs to be confident of the lighting and visual effects these will have.

For quantitative analysis, numerical processing of the LuxRender images will be done with Radiance, an accurate but more difficult to use software programme. This avoids the complex use of Radiance for image generation, but utilises it appropriately for its excellent numerical analysis capabilities, and constitutes a custom, simplified and effective workflow.

The formation of this complete workflow from lighting data acquisition, through visualisation and analysis, to design response (with relevance to students’ design studio throughout) maximises the potential of this technique to meld the scientific with the aesthetic, and fully engage students with the environment and design aspects of their discipline.

The use of low cost or free hardware and software, the publishing of the learning materials, and the environmental nature of the project makes the outputs applicable and of interest to a wide range of courses and institutions. To maximise uptake the project will create a website which links into existing web-based HDR resources but also provides a focused repository and learning resource for what will be called HDR Imaging in Design Education (HIDE).