For reasons unknown, when using scattering I had it as: f.ipm=f.scattering[:-1] in Controller() This was probably and inherited indexing problem from other parts of the code and beamtime troubleshooting. It should just be the full range. <img width="771" height="565" alt="Image" src="https://github.com/user-attachments/assets/0387f837-bf66-4d67-b401-b80eb9f42255" />