Hi Mark,
yes. however arp/warp has lost this ability in the ccp4i "classic" mode.
Oh, too bad. I wrote a small mtz_free_flipper.py script that will be part of the next CCI Apps maintenance release (hopefully tomorrow). If you want to use it right now, get the current cctbx bundle from here: http://cci.lbl.gov/cctbx_build/all.html Build tag: 2008_05_02_0119 (or later) Pick a bundle from the "cctbx+Python" column. You can install it anywhere, e.g. in /var/tmp/junk. After the perl cctbx*.selfx command is finished (a few seconds), source the setpaths script for your shell as usual, then run this command: cctbx.python cctbx_sources/iotbx/iotbx/examples/mtz_free_flipper.py your.mtz It will write a file free_flipped_your.mtz. The script assumes the R-free flags column label is "R-free-flags". If your label is different, copy the example script, modify the label (should be obvious) and run the modified script: cctbx.python copy_of_mtz_free_flipper.py your.mtz Note: the script will not work with the current CCI Apps because I had to add something to the mtz module last night to keep the script simple. Ralf