[ccp4bb] Fwd: [ccp4bb] : MTZ for a protein fragment and R factors, Masking and Maps

2014-06-05 Thread Patrick Loll
George, Remember that scattering from every point in the cell contributes to every reflection; the R-value is a global metric of agreement between the model and the data. Hence, calculating the R-value for a few selected residues is not a sensible thing to do, unless you want to ask how well yo

Re: [ccp4bb] : MTZ for a protein fragment and R factors, Masking and Maps

2014-06-05 Thread Paul Emsley
On 05/06/14 16:10, George Devaniranjan wrote: Hi, First off I am pretty new to CCP4/X-ray crystallography so please bear with me as I try to explain my question. I was looking at a protein structure from the PDB (let's say 1aho.pdb). I have the corresponding MTZ file. I wanted to calculate t

Re: [ccp4bb] : MTZ for a protein fragment and R factors, Masking and Maps

2014-06-05 Thread Mark J van Raaij
Hi George, The R-factor is an overall disagreement statistic, it can not be broken down in parts for bits of the structure. (in other words, you can not correlate parts of the model with a subset of the reflections in the mtz, as a non-crystallographer might think - all the electrons in the as

[ccp4bb] : MTZ for a protein fragment and R factors, Masking and Maps

2014-06-05 Thread George Devaniranjan
Hi, First off I am pretty new to CCP4/X-ray crystallography so please bear with me as I try to explain my question. I was looking at a protein structure from the PDB (let's say 1aho.pdb). I have the corresponding MTZ file. I wanted to calculate the R-factor for some selected residues (lets say 1