javascript - Heatmap gradient changes when multiple nearby sources? -

here heatmap 1 source (weight=0.3) :

and here heatmap multiple sources (weight=0.3) :

i use heatmap represent pollution level. , when have 4 sources weight of 0.3 (image2) expect same green color on image1.

but because heatmaps used represent density, add these sources weights.

how can prevent happening?

note: using google maps api

i think want use maxintensity. documentation:

maxintensity: maximum intensity of heatmap. default, heatmap colors dynamically scaled according greatest concentration of points @ particular pixel on map. property allows specify fixed maximum. setting maximum intensity can helpful when dataset contains few outliers unusually high intensity.

the more points add, more intense heatmap be. therefore, if don't want color change, can specify low maximum intensity green.