Hi Enrico, For the first point, you can use this command mm ~#1 to #1. For the second point, if you know which atoms you want to align along z, you can use view zalign atom-spec-1 atom-spec-2 Best, Matthias From: Enrico Martinez via ChimeraX-users <chimerax-users@cgl.ucsf.edu> Date: Wednesday, February 12, 2025 at 19:15 To: ChimeraX Users Help <chimerax-users@cgl.ucsf.edu> Subject: [chimerax-users] Questions about match and view commands Dear ChimeraX users! I am performing a visualization of the ensemble of conformers for the same protein defined in the chimerax as models #1 to #6. Here are some of my questions: 1 - I try to superimpose all structures to the first model using match #2-5 to #1 is it possible to use some regular expression instead of #2-5 to select all models from the second to the last e.g. to superimpose all structures to the first one in the script. 2 - I try to automatically orient the superimposed models along its principal axe in one command e.g. using view orient but it does not produce a proper orientation. What kind of trick could work for a nanobody object to orient it automatically e,g, along Z ? Many thanks in advance Enrico