In Sports Lighting, the two main parameters that determine the quality of lighting are the Average Illumination and the level of Uniformity.
These two values are closely related to each other, that is: with the same number of spotlights and the same power, we can light a sports court in different ways, that is, increase the average illumination by reducing the uniformity or vice versa.
The explanation is simple: to achieve greater average lighting, we have to find a way to put all the lumens (unit of light) emitted by the spotlights inside the track, preventing as few as possible from being lost; In this way, we will focus all the spotlights towards the center of the track, with which we would have a lot of light in the center, little in the corners and, therefore, a very high average illumination, in exchange for a very low uniformity. On the contrary, if we are looking for a good uniformity, we would have to make each spotlight illuminate a part of the track, looking for all the parts to receive the same lighting; in this way not all the lumens would fall inside the track, some would come out of it. Thus we would have a good uniformity in exchange for lowering the average illumination.
The interesting thing is always to seek balance, it is useless to have a track with a very high average lighting, if we have areas that are almost dark, and on the contrary, we can have a very good uniformity, but we may not reach the level of average lighting that sets the standard for this type of installation.
But this is better seen with a practical example. Let’s take a 20x10m paddle tennis court, with 4 6m towers, and put 2 of our 150w LED spotlights on each of them, and only by varying their orientation, let’s see what happens with the average lighting and uniformity.
BEWARE!, studies carried out with FM=0.80 as indicated by UNE-EN 12193. If we used higher values (as the vast majority do), the lighting results would also be higher.
Seeking maximum Average Illumination
Looking for the maximum Uniformity
an extreme case
We would get:
I. Average Illumination: 416lx
Concentrating the light in the center of the track. By not letting light “escape” out of it, we achieve a very high value in average lighting.
We would get:
I. Average Illumination: 344lx
Unlike the previous one, each spotlight shines on an area within the track; the uniformity improves, on the other hand the Illumination drops to 344lx.
We would get:
I. Average Illumination: 497lx
Comment: For this case, we have used the same spotlight, only the version with 30ºx70º optics (a more concentrated beam of light), which allows us to concentrate the light even more in the center. Lighting shoots up and uniformity plummets. The corners are dark.
From here some quick conclusions. To increase the average illumination without compromising uniformity, more powerful spotlights must be mounted. Uniformity can be improved by installing more spotlights, the greater the number of spotlights, the easier it is to distribute the light on the track; Another option is to change the light angle of the bulbs, looking for one that allows us to distribute the light more evenly.
We hope this article has been of interest to you, if you have any questions please call us at 688 902 900 and we will be happy to assist you.