Footprints™
Footprints™ is our iso-illuminance template generator, available here free of charge.
The software is quick and easy to use for those familiar with basic lighting terminology and Windows operations. If you don't already know how to create a folder or how to download a file from the internet, or if you don't know the difference between a lumen and a footcandle, it would be a good idea to have someone in your office explain these to you before attempting to install and utilize this software.
Already installed the software but now you have some questions? If this is your first time using a template generator our online tutorial will be of help; more advanced users will find answers to their questions on our FAQ page.
What is a Template?
Iso-illuminance templates are generally used for outdoor applications like parking lots and roadways. The diagram illustrates the area of coverage (footprint) of a given pole assembly, and is often all that's needed to produce an acceptable site lighting design. Iso-illuminance lines are analogous to the contour lines representing change in grade on a topography map. Higher levels are generally found near the pole (the peak), with levels falling-off as you move further away.
If
one pole is producing 1.0 footcandle (fc) of horizontal illuminance
at a point, and another pole produces 0.5 fc there, the two poles
simply combine to produce 1.5 fc at that point. Similarly, if
you're designing to 0.5 fc minimum and the 0.25 fc curve from
one pole meets the 0.25 fc curve from another pole, you're meeting
your criterion at the intersection. In this way, templates can
be "pushed around" and arranged on a site plan to insure adequate
coverage.
Templates are useful when designing to a minimum horizontal illuminance criterion. If you need to meet an average horizontal illuminance requirement you MUST run a point-by-point calculation; templates cannot be used to determine average levels. Similarly, if you need to meet a minimum vertical illuminance criterion, you must run a pt x pt.
Each
template uniquely describes a given ies File-Lumens-
LLF-Arrangement-Height-
Arm-Tilt-Scale-Isolines
combination. If you change any parameter you will need to generate
a new template. In the "good-old days" manufacturers would provide
a binder full of templates of each luminaire for varying mounting
heights. As you will see, quick and easy-to-use software like Footprints™ renders such physical media obsolete.
