xirrus cartography of light emissions

Site Analysis

An initial global or regional analysis can find the spots of unnatural brightness at night. Then, our site analysis cartography makes maps of the light sources in charge. Using this aerial view, discussion with light planners and originators about actions to take, becomes much easier and clear.

For a natural preserve, for example ten bright sites can be analyzed and evaluated, and a resulting report serves as a basis for further discussion. The work procedures have been assessed and optimized ever since its first on-site application in 2018.

Example Section of a Map

The middle part depicts a processed image, which mimicks the human perception of light and colour, which also lifts out very dark and very bright details. The trees in the dark, top left, and the pedestrian crossing in the bright center, become perceptible.

The false-colour imagery on the right quantifies the luminance in an abstract fashion.

160 m side length per image, resolution (original) ca. 5 cm

Suitable sites for such an analysis are, for example:

• industrial plants and commercial areas
• shopping malls
• illuminated buidlings and landmarks
• sports grounds and stadiums
• road sections

Usually, areas up to 25 ha can be covered in one go.

Publicly accessible site with many light source, 500 m side length

From such maps, priorities can be derived for an action plan.

Additional measurements on the spot can be performed, in order to check the quality of light sources, or the conformity to norms and standards. Those measurements include:

• luminance
• spectral analysis, colour representation, colour temperature
• illumination level, immission limits
• local brightening of the sky

Our specialist care about the operative details like planning, training, permits and negotiations (subject to restrictions due to power lines, wind plants, proximity to airports or missing permits). Depending on season, weather, moon phase and ease of obtaining permits, such analyses will take a duration of about one to four months, although the actual on-site efforts are much shorter.

The results are summarized in a report. Raw data, presentations, project support or consultancy are available as options.

Pricing will be estimated in advance, considering amount of analyses, size of the area, complexity, and surroundings.