Glare Analysis

Luminance based analysis methods have been historically difficult to conduct in scenes with daylight due to expensive equipment and the variable nature of scenes with daylight. Hand held luminance meters are not only expensive but it is difficult to record data in a space with daylight in a comprehensive manner before the daylight conditions change. High Dynamic Range photography techniques have made access to luminance data from real daylit spaces far more feasible to generate and computational methods are facilitating rapid development of new luminance based analysis metrics. These techniques have been available in digital daylight simulations for many years but the development of these techniques for real spaces is more recent.

The images above reveal the potential of luminance based analysis methods. In these images simple luminance ratios are shown for a space that a user rated as ‘preferable’ on the left and for a space the same user rated as ‘just disturbing glare’ on the right.

Advanced computational methods allow designers to examine real spaces and digitally simulated spaces with emerging luminance based metrics to assess visual comfort and aspects of quality. However, there is currently very little guidance for designers seeking to refine design solutions based upon these metrics because it is still an emerging research area.

• A Study of Luminance Distribution Patterns and Occupants’ Preferences in Daylit Offices, Passive and Low Energy Architecture, Annual Conference Proceedings, June 2009, Québec City, Canada; Kevin Van Den Wymelenberg, Mehlika Inanici