I'm quite new to the ArcGIS suite and have mostly muddled my way through ok so far but this has me stumped. I am trying to compare the event-probability distribution of two KDE heatmaps. This is done by first normalising the maps such that the sum of all elements add to 1. This means that each pixel has some very small associated value that represents the likelihood of an event happening at that point. The distrubitions of these maps are compared by subtracting the maps from each other. The final maps have values ranging from some very small negative value to some very small positive value. I'd then like to plot this difference map with a classified colour map that is symmetrically arranged about zero. However I cannot seem to work out how to do this as ArcGis will not let me arrange the break values beyond the minimum value of the dataset. I realize that setting break values this way means that there will be redundant, unused colours but it seems necessary for presentation purposes. Is there an easy way to do this? Or am I better off to simply export the rasters into python and do my plotting there?