I think there is a misconception floating around that processing your
data with "anomalous turned on" will somehow degrade the quality of
"normal" intensity data.  I'm not exactly sure where this rumor comes
from, but I imagine it has something to do with confusion about all
the various "anomalous" options different scaling programs have.  For
example, some programs offer the option to treat all I+ and all I- as
completely separate data sets, scaled and merged independently.  I
think this is called "scale anomalous" in SCALEPACK and "intensities
anomalous" in SCALA.  Neither of these is the default because such
treatment is only helpful if the anomalous signal is absolutely huge
(I have only seen this once).  So, I imagine people who have never
done experimental phasing (there are lots of them!) might read things
like "Switching ANOMALOUS ON does affect the statistics and the
outlier rejection" in the SCALA manual and decide that they had better
turn off all those evil "anomalous" things.  Then they tell their
students to do the same, etc.

-James Holton
MAD Scientist


On Tue, Jun 12, 2012 at 3:17 AM, Eleanor Dodson
<eleanor.dod...@york.ac.uk> wrote:
> Why would anyone ignore the anomalous data they had collected? It will always 
> help the phasing, and decide the hand for you..
>  Eleanor
> On 6 Jun 2012, at 03:55, Stefan Gajewski wrote:
>
>> Hey!
>>
>> I was just wondering, do you know of any recent (~10y) publication that 
>> presented a structure solution solely based on MIR? Without the use of any 
>> anomalous signal of some sort?
>>
>> When was the last time you saw a structure that was solved without the use 
>> of anomalous signal or homology model? Is there a way to look up the answer 
>> (e.g. filter settings in the RCSB) I am not aware of?
>>
>> Thanks,
>> S.
>>
>> (Disclaimer: I am aware that isomorpous data is a valuable source of 
>> information)

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