[phenixbb] regarding ncs distance - .geo file

Nathaniel Echols NEchols at lbl.gov
Mon Nov 23 07:24:35 PST 2009

On Nov 23, 2009, at 12:02 AM, Pavel Afonine wrote:
> just to remove some of my ignorance,...  and sorry in advance for a 
> stupid question:  What is "(...) Dano maps in CCP4 using phases from 
> your current model (...)". If you tell me exactly what it is I might be 
> able to add this to PHENIX family of tools (or at least put it to to-do 
> list)...

The existing tools already do this.  Some CCP4 (or associated) programs preserve the anomalous differences as a separate pair of columns DANO,SIGDANO, even when the original F+/F- have been averaged together and are no longer present in the file. (I don't know why this is considered a good idea, but I have files to prove it...) So you can take DANO and PHI from another file and make an anomalous difference map.  I think that's what Mark was talking about - it's a little confusing, because if I recall correctly ccp4i allows you to make two types of anomalous map, and I think the difference is whether you use F+/F- or DANO.

We could probably add a feature to combine DANO and model phase information, but if F+/F- are present this is unnecessary - and everyone should really keep the anomalous data handy anyway.

Nathaniel Echols
Lawrence Berkeley Lab
NEchols at lbl.gov

More information about the phenixbb mailing list