 |
 |
Hi Mani, Yes: maps should have higher than 10A resolution for automated B-factor correction. The reason why is explained in Rosenthal&Henderson 2003: from 10A onwards the Guinier plot of molecules becomes flat, which is what we use for finding the B-factor. If you have less than 10A resolution, than you should use the --adhoc_bfac to sharpen your map. However, at 18A resolution, sharpening will probably not make such a big difference... HTH, S On 10/25/2013 10:54 AM, Manikandan KARUPPASAMY wrote: > Hi Sjors, > > Please ignore the previous incomplete email. > > I would like to know why we are not getting any estimation of B-factor. > > ****** > == Fitting straight line through Guinier plot to find B-factor ... > + fit from resolution: 10 > + fit until resolution: 0 > + slope of fit: -nan > + intercept of fit: -nan > + correlation of fit: -nan > == Low-pass filtering final map ... > + filter frequency: 16.1418 > ****** > > I run the postprocess as follows > > $relion_postprocess --i Refine3D/run1_ct13 --o > Refine3D/postprocess_run1 --angpix 5.79 --auto_mask --auto_bfac > > > Do maps should have resolution higher than (<) 10 A for the B-factor > estimation? > > The current resolution of the map is about 18 A. > > with kind regards > > Mani. -- Sjors Scheres MRC Laboratory of Molecular Biology Francis Crick Avenue, Cambridge Biomedical Campus Cambridge CB2 0QH, U.K. tel: +44 (0)1223 267061 http://www2.mrc-lmb.cam.ac.uk/groups/scheres