import arcpy mxd = arcpy.mapping.MapDocument("CURRENT") df = arcpy.mapping.ListDataFrames(mxd, "*")[0] # grab 1st dataframe in map #df = arcpy.mapping.ListDataFrames(mxd, "Main")[0] # grab dataframe named 'Main' arcpy.MakeMosaicLayer_management( 'Orthophotos', # input mosaic 'test_mosaic', # output mosaic '#', # Optional WHERE clause df.extent # clipping box coordinates )