Night Light of Langfang (Hebei) from space (China) Src. Average luminocity for 10x10km area is 82.125% and for 50x50km: 25.4614%.
Square area 10x10 km:
 28.57%
 28.57% 21.27%
 21.27% 10.39%
 10.39% 16.07%
 16.07% 8.77%
 8.77% 6.82%
 6.82% 2.44%
 2.44% 2.44%
 2.44% 2.76%
 2.76% 0.49%
 0.49% 0%
 0%Square area 50x50 km:
 1.97%
 1.97% 2.2%
 2.2% 4.23%
 4.23% 3.76%
 3.76% 3.97%
 3.97% 4.42%
 4.42% 4.97%
 4.97% 6.6%
 6.6% 7.62%
 7.62% 16.44%
 16.44% 43.82%
 43.82%Clear (daylight) street map image can be seen on geolist.org.
Map coordinates:
40° 3' 0.3" North, 115° 59' 29.8" East
39° 30' 35" North, 116° 41' 41" East
38° 57' 54.5" North, 117° 23' 52.3" East
Some cities around Langfang sort by population:
• Tongzhou
		43.9 km =27.3 mi,  356°
356°
• Daxing
		40.6 km =25.2 mi,  309°
309°
• Yangliuqing
		49 km =30.4 mi,  147°
147°
• Yangcun
		35.3 km =21.9 mi,  117°
117°
• Beicang
		47.8 km =29.7 mi,  129°
129°
• Hanjiashu
		48.4 km =30.1 mi,  137°
137°
• Qingguang
		45.2 km =28.1 mi,  139°
139°
• Dakoutun
		46.5 km =28.9 mi,  79°
79°
Sources (retrieved 2019-11-25):
» NASA, Earths city lights 1995
» NASA city lights 2003
» Earth at Night: Flat Maps 2012, 2016