Hi Chimerax Group, I am trying to measure the distance between two atoms in a protein in Chimerax v1.4. The .pdb file I am working with was generated using Alphafold2 in the ColabFold application. I select the two atoms by using CTRL+SHIFT, go to the TOOL -> Structure Analysis -> Distances. The Structure Measurements panel appears in the lower right of the screen. When I click on the Create button, a Chimerax box appears on screen with the following message: Exactly two atoms must be selected! I was surprised to see this message since I thought I had properly selected two atoms. Any advice on how to calculate the distance would be greatly appreciated. Thanks in advance for any help you can provide. Phil McClean Professor North Dakota State University