Simulated-1g1c: Difference between revisions

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=== Towards better completeness: using the first two frames ===
=== Towards better completeness: using the first two frames ===


We might want better (anomalous) completeness than what is given by only the very first frame of each dataset. To this end, we change in XDS.INP :
We might want better (anomalous) completeness than what is given by only the very first frame of each dataset. To this end, we change in the XDS.INP part of our script :
  DATA_RANGE=1 2
  DATA_RANGE=1 2
and in XSCALE.INP we insert
then run the script which reduces the 100 datasets. When this has finished, we insert in XSCALE.INP  
  NBATCH=2  
  NBATCH=2  
after each INPUT_FILE line. The reason for this is that by default, XSCALE establishes scalefactors every DELPHI (default: 5) degrees, but here we want scalefactors for every frame, because the radiation damage is so strong. This gives:
after each INPUT_FILE line (this can be easily done using <pre> awk '{print $0;print "NBATCH=2"}' XSCALE.INP > x </pre>). The reason for this is that by default, XSCALE establishes scalefactors every 5 degrees, but here we want scalefactors for every frame, because the radiation damage is so strong. This gives:
       NOTE:      Friedel pairs are treated as different reflections.
       NOTE:      Friedel pairs are treated as different reflections.
   
   
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     total      165827  42032    43003      97.7%      12.8%    13.3%  162426    8.79    14.7%    15.7%    15%  0.881  16225
     total      165827  42032    43003      97.7%      12.8%    13.3%  162426    8.79    14.7%    15.7%    15%  0.881  16225


showing that the anomalous completeness, and even the quality of the anomalous signal, can indeed be increased. I doubt, however, that going to three or more frames would improve things even more.  
showing that the anomalous completeness, and even the quality of the anomalous signal, can indeed be increased. I doubt, however, that going to three or more frames would improve things even more.
 
The MTZ files are at [ftp://turn5.biologie.uni-konstanz.de/pub/xds-datared/1g1c/xds-simulated-1g1c-F-2frames.mtz] and [ftp://turn5.biologie.uni-konstanz.de/pub/xds-datared/1g1c/xds-simulated-1g1c-I-2frames.mtz], respectively. They were of course obtained with XDSCONV.INP:
INPUT_FILE=temp.ahkl
OUTPUT_FILE=temp.hkl CCP4_I
for the intensities, and
INPUT_FILE=temp.ahkl
OUTPUT_FILE=temp.hkl CCP4
for the amplitudes. In both cases, after xdsconv we have to run
<pre>
f2mtz HKLOUT temp.mtz<F2MTZ.INP
cad HKLIN1 temp.mtz HKLOUT output_file_name.mtz<<EOF
LABIN FILE 1 ALL
END
EOF
</pre>


=== Why this is difficult to solve with SAD phasing ===
=== Why this is difficult to solve with SAD phasing ===
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