Photometry is the science concerned with measuring visual response to light, in terms of its perceived brightness to the human eye. Because the eye is a highly complex organ, this is by no means a simple task.
OK, that's a simplified definition, without the formulas & technical issues that drive the work.
Depending on your point of view, photometry is either the glamorous scientific side of a lighting designer's efforts to create great lighting OR the quite less-than-sexy work to make a design function correctly by providing the correct levels of light to meet a code or need. From either view, the resulting renders that are part of the engineering of photometry are both informative and cool.
Earlier this year I was asked to design an exterior lighting package for a restoration project of a city block in Bennington VT. Working with a design team of Stevens & Associates & the engineering firm of Dubois & King, we designed & engineered for public street entrances, rear building entries, two public courtyards and off-street parking & access ways. The final photometric renderings by Dubois & King illustrate the results beautifully. Bright entries that beckon you to approach & provide abundant safe lighting at sidewalks & steps, courtyards that invite you to hangout & relax in them, and parking with a relatively even wash of light. This was another wonderful collaboration, very happy to be a part of the teamwork!