Dear all! I am not sure if this is the correct place to ask beginner-questions, how to use cctbx, but I try anyway. I would like to read in a mtz file, and convert it to a density map, which I can modify in real space using the asymmetric unit, and afterwards I would like to convert my modified map back to an mtz file. Currently I am stuck at the point, where I want to reduce the map from the unit cell to the asymmetric unit. from iotbx import mtz from cctbx import miller mtz_filename="./some_mtz_file.mtz" mtz_file = mtz.object(mtz_filename) Miller_array = mtz_file.as_miller_arrays() NEW_ARRAY=Miller_array[0].phase_transfer(Miller_array[1], deg=True) #by the way: what can I do with the mandatory_factors flag? Does grid_step=1 means the grid as a 1A spacing? FFT_map = NEW_ARRAY.fft_map(grid_step=1) Real_map = FFT_map.real_map() I would be happy, if anybody could give me some advice how to do that using the cctbx libaries! Thanks in advance Regards Philipp -- -------------------------------------------------- Dr Philipp Heuser Postdoctoral fellow EMBL-Hamburg c/o Building 25A, DESY Notkestrasse 85 22603 Hamburg phone: +49 40 89902 188 fax: +49 40 89902 149 mail: [email protected] --------------------------------------------------