[Chimera-users] fit molecule with Laplacian filtered map

Hello, This is my first time trying to apply the Laplacian filter to a cryo-EM map in Chimera before I perform the global search to fit my crystal structure. However, the resulting map looks like the original map blown up into million pieces with positive and negative density showing. I get the same effect even after I "smooth" the map with the Gaussian filter first. Could someone advise me on how I could use this Laplacian filtered map information to better fit my molecule into the original EM map? Thanks for your help in advance. Noboru