Hi all, I'm trying to calculate a composite omit map so that I can get a clear view of a troublesome region in my structure. I have two copies of everything in the asu so I created some dummy atoms to mask the region in the A chain and called those atoms chain Y and another collection to mask the region in the C chain and created a Z chain for them. I put these atoms in a file name Mask.pdb I attempted to calculate the composite omit map starting from my MR solution but that fails because Autobuild doesn't like being given the Fourier coefficients produced by Phaser. To work around this problem I decided to ask it to create the omit map based on the results of my AutoBuild followed the MR. My script is: phenix.autobuild model=AutoBuild_run_12_/overall_best.pdb data=1M50-2.mtz \ input_refinement_labels="FP SIGFP None None None None None None FreeR_flag" \ seq_file=../fmo-ct.pir \ resolution=2.2 dmax=20 refinement_resolution=2.2 \ cif_def_file_list=/usr/users/dale/geometry/chromophores/bcl_tnt.cif \ input_lig_file_list=AutoMR_run_4_/MR.1-Bchl-a.pdb \ composite_omit_type=iterative_build_omit omit_region_specification=omit_around_pdb omit_box_pdb=Mask.pdb\ omit_res_start_list="1 1" omit_res_end_list="39 30" omit_chain_list="Y Z" \ rebuild_in_place=Yes Mask.pdb is attached. Resolve is unable to create a mask. The log file, omit_box_id.log is also attached. Resolve creates a temp file named TMP.pdb which I would expect to contain the contents of my Mask.pdb. It only contains the first set of dummy atoms; chain Y. Then when Resolve reads this file it appears not to find even those atoms. I know Tom is out of reach for quite a while. Is there someone else who could help me over this hurdle? Dale Tronrud