Dear SPM experts I have 2 questions. 1. how to display both surface with thickness in same figure ? I only can display single hemisphere with thickness in one figure. 2. I use display surface result function and select one surface. but I get error message Error using cat_surf_results (line 414) No data in surfaces found. Error in cat_surf_results>select_data (line 1633) cat_surf_results('disp', H.S{1}.name, H.S{2}.name); Error while evaluating DestroyedObject Callback actually I have surface and thickness data. why I get this error message ? thank your answer JLH