Why do you detwin? It would not be normal procedure if you have twinning. Molecular replacement programs usually do not have much problem with twinned data and refinement programs can deal with them more or less properly. when you detwin then errors are increased (As far as I remember proportional to 1/(1-2alpha), if alpha is 0.46 then errors will increase more than 10 times). Moreover it is very likely that twin and pseudo rotation are close to each other and estimated twin fractions may not be accurate.
regards Garib On 29 Sep 2011, at 15:03, Yuri Pompeu wrote: > After I ran DETWIN with the estimated 0.46 alpha, my completeness for the > detwinned data is now down to 54%!!! > Is this normal behavior? (I am guessing yes since the lower symmetry > untwinned dat is P1 21 1) Garib N Murshudov Structural Studies Division MRC Laboratory of Molecular Biology Hills Road Cambridge CB2 0QH UK Email: ga...@mrc-lmb.cam.ac.uk Web http://www.mrc-lmb.cam.ac.uk
