Table 3. Performance of atlas predictions for different data sets.
Negative values indicate that the observed skies were brighter than predicted. The top entries are used to calibrate the atlas. The final three entries are independent data sets used for verification. PS, professional scientist; CS, citizen scientist.
| Provider | Location | Mode | Mean | σ | Scientist |
| All data | Worldwide | Both | 0.008 | 0.17 | Mixed |
| Various | Catalonia, Spain | Car | 0.03 | 0.14 | PS |
| Universidad Complutense de Madrid | Madrid, Spain | Car | −0.04 | 0.17 | PS |
| Kyba/Sanchez | Berlin, Germany | Car | 0.12 | 0.11 | PS |
| Globe at Night | Worldwide | Hand | −0.21 | 0.34 | CS |
| Haenel/Frank | Europe and North America | Hand | 0.05 | 0.17 | PS |
| Unihedron | Worldwide | Hand | −0.01 | 0.24 | CS |
| Loss of the Night app | Worldwide | Hand | −0.02 | 0.29 | CS |
| Espey/Owens | Ireland | Hand | −0.08 | 0.14 | Mixed |
| Royal Astronomical Society of Canada | Canada | Hand | −0.01 | 0.28 | CS |
| Giubbilini | Italy | Hand | 0.03 | 0.09 | PS |
| International Dark Sky Places | Wales | Hand | 0.01 | 0.27 | CS |
| U.S. National Park Service | United States | CCD | 0.11 | 0.13 | PS |
| Falchi | Italy | CCD | −0.04 | 0.19 | PS |
| SQM stations | Worldwide | Permanent stations | −0.06 | 0.46 | Mixed |