Re: [ccp4bb] Refmac5 and Pseudo-merohedral twinning

2009-03-12 Thread Garib Murshudov
Current version does not expand data or model. C222 twinned in P2 will not be handled if data are in C222. Overmerged data are a bit tricky to deal with. And model in higher space group would not fit into the asymmetric unit in general. In short: in the current version space group should be a

Re: [ccp4bb] Refmac5 and Pseudo-merohedral twinning

2009-03-12 Thread Frank von Delft
Hi Pavol, Garib Actually, that bit of doc doesn't answer a few practical questions we keep running into: 1) What spacegroup should you provide the data in? The usual scenario, in practice, is that one merges in too high symmetry, and wants to check whether it is actually lower symmetry with

Re: [ccp4bb] Refmac5 and Pseudo-merohedral twinning

2009-03-12 Thread Pavol
Dear Kim, yes, Refmac handles pseudo-merohedral twinning. The procedure is fully automatic and there is not much to change but the documention can be found here: http://www.ccp4.ac.uk/html/refmac5/keywords/keywords_5_5.html#Twin Pavol

[ccp4bb] Refmac5 and Pseudo-merohedral twinning

2009-03-12 Thread Kim, Walter
Hi, I am currently trying to work with perfectly twinned data and have a starting model that I found through phaser. In trying to refine the model against the data, I noticed that Refmac5 has a "twin refinement" option that performs some sort of automatic refinement against the found twin laws