Hi Tim,
(1) Of course, the specifiers must be correct for the atoms and/or centroids in your structure.  You probably have that right but I can't check it because I don't have your exact data.

(2) The "distance" command to show the distance does not have a setDefaults option.  To use that option you have to use a separate "distance style" command.  This is shown in the usage lines on the "distance" help page:
<https://rbvi.ucsf.edu/chimerax/docs/user/commands/distance.html>

Since you are not setting defaults, it will probably work if you just omit the "setDefaults false" part.

I hope this helps,
Elaine
-----
Elaine C. Meng, Ph.D.                       
UCSF Chimera(X) team
Resource for Biocomputing, Visualization, and Informatics
Department of Pharmaceutical Chemistry
University of California, San Francisco


> On Feb 1, 2026, at 7:37 AM, Timothy Springer via ChimeraX-users <chimerax-users@cgl.ucsf.edu> wrote:
>
> What is wrong with this second line:
> define centroid  #1/A:214@CD1, CD2, CE1, CE2, CG, CZ radius 0.075
> distance #1.3 #1/V:38@NE2 setDefaults false color black dashes 6 radius 0.04
>
> - Tim
> Timothy A. Springer, Ph.D.
> Latham Family Professor, Harvard Medical School and Boston Children's Hospital
> Founder, Institute for Protein Innovation