Hi Natalie, This is a ChimeraX question, although sent to the chimera-users list -- although unnecessary this time, for future reference please send chimeraX questions to the chimerax-users@cgl.ucsf.edu list CC'd here (we try not to confuse Chimera users with ChimeraX answers and vice versa). The instructions of how to open MTZ files with ChimeraX are here: <https://rbvi.ucsf.edu/chimerax/docs/user/commands/open.html#clipper> "Opening an MTZ file requires specifying an already-open atomic structure with the structureModel option..." with example command, etc. I hope this helps, Elaine ----- Elaine C. Meng, Ph.D. UCSF Chimera(X) team Department of Pharmaceutical Chemistry University of California, San Francisco

On Jul 3, 2023, at 8:52 AM, Natalie Walsh via Chimera-users <chimera-users@cgl.ucsf.edu> wrote:

Hello,

I am having troubles opening MTZ maps from PDB on ChimeraX 17.1. on Mac OS. I read somewhere that you need to download the Clipper plug-in. I went ahead and installed that (although I am not sure that I was successful) and am still struggling to open these files.

Thank you, Natalie Walsh