I am working on InSAR DEMs. In ArcMap (version 10.1), I took two input DEMs(both having elevation and coherence bands). I created a model in ArcMap model builder to obtain a better elevation value for each pixel in the input images. I am using the "Con" tool in the Raster Calculator to select the larger coherence value of the two and select the corresponding elevation value for my output. But as checked using identify tool at random points of my output it is found that at some points, the output is totally different from both the input values (kindly refer to the image attached, here, "delev12" and "DEM4" are the inputs and "Delev_O1_D4" is the output). I am unable to understand the reason behind this, as no arithmetic operation is performed only values are selected, then why does output contain a different value?