Hi,
It used to be that if one ran global refinement on a symmetry expanded particle set, a truly crazy FSC would result, because the symmetry expanded copies would end up correlating perfectly with one another (presumably because they were randomly divided between the half-sets at assignment).
At some point this changed, and one can now run a global refinement of a sym-expanded particle set and get an apparently normal FSC. I assume that what happened is that the convention was changed such that all the sym expanded copies of a given particle inherit the half-set identifier of the parent particle, but I’m not sure that was ever stated anywhere explicitly (apologies if I missed it!).
Am I correct in that assumption, or is something else going on?
Cheers
Oli
hi @olibclarke ,
I went down a symmetry expansion rabbit hole somewhat recently, and unless you re-do the half-sets, my understanding is they should stay together (see here, which was 2021, so not sure how far back you’re referring to).
Interestingly though, I was trying to make some egregious FSCs for a presentation I was giving recently, and it was surprisingly difficult, even with high symmetry and re-doing half sets, to make some of the curves I was trying to make. I was hoping it would be a little more obvious when you do something terribly wrong 
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Ah thanks! Yes that’s what I assumed was going on, although I (maybe mistakenly) thought that it wasn’t always so - good to know!
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Hi @olibclarke and @tlevitz! We recently changed the default setting of Force re-do GS split to false / off for all global refinements (it used to default to true / on except in Local Refinement). One of the effects of this is that global refinement of symmetry expanded particles (while still not our recommendation) should be a bit more resilient in terms of GSFSC.
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Ahaha! I thought something had changed, good to know, thanks @rwaldo 
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