I think it used to be "default" in denzo/scalepack. Or perhaps it was used to 
calculate statistics, but not to exclude reflections...I do remember having to 
"switch it off".





On 14 Nov 2013, at 12:29, Phil Evans wrote:

> Always deprecated, hopefully never common!
> 
> 
> 
> On 14 Nov 2013, at 11:27, Mark J van Raaij <[email protected]> wrote:
> 
>> It used to be common to only include reflections for which I > x sigma(I) in 
>> refinement, with x often being 3.
>> However, nowadays this is not considered good practise, as reflections with 
>> small Is are likely to have I < 3 sigma(I), but are also important for 
>> refinement.
>> 
>> In small molecule crystallography I think it is still common to have a sigma 
>> criterion.
>> 
>> if, in this respect, you have used default settings in data reduction and 
>> refinement, you should select "none" or "n.a." in the deposition process.
>> 
>> Mark J van Raaij
>> Lab 20B
>> Dpto de Estructura de Macromoleculas
>> Centro Nacional de Biotecnologia - CSIC
>> c/Darwin 3
>> E-28049 Madrid, Spain
>> tel. (+34) 91 585 4616
>> http://www.cnb.csic.es/~mjvanraaij
>> 
>> 
>> 
>> 
>> 
>> On 14 Nov 2013, at 12:06, Faisal Tarique wrote:
>> 
>>> Dear all
>>> 
>>> I request you to please explain the "Observed criterion sigma" value
>>> required during pdb deposition. Does it depends on the methods of data
>>> integration and scaling ? if yes then what are the values for the data
>>> processed through scalepack2mtz (HKL2000) and scala (mosflm)..
>>> 
>>> -- 
>>> Regards
>>> 
>>> Faisal
>>> School of Life Sciences
>>> JNU

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