Hi @rpiwowarcz, thanks for confirming. I see what you meant about the UIDs earlier – you’re right that they are different when the particles are re-imported.
If you didn’t perform higher-order CTF estimations earlier in your workflow, the CTF information (including per-particle defocus) should remain the same after re-importing from RELION, so you shouldn’t need to re-connect the CTF from an earlier refinement.
If you did perform higher-order CTF estimations, the easiest way to recover these is probably using CryoSPARC Tools to set the UIDs of the re-imported particles to be the same as the original particles, then use the low-level interface to replace the CTF values of the resulting UID-corrected particles. You can find an example to reset the UIDs here.
You could also modify that script to replace the CTF values directly rather than use the UIDs, if you prefer.
I hope that’s helpful!