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[ccp4bb]: Denzo v. Mosflm

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I am refining a structure with synchrotron data that has been processed by
denzo_3d/scalepack. I have refined it nearly as far as I can go to 3.2 A,
but my stats look like I should be able to get more out of this data (at
least push it to 3.0 Angstroms). The crystal is somewhat mosaic (0.67 deg),
diffracts anisotropically, and has a fairly large P2(1) unit cell (101.034
94.764 112.878 Ang.). The I/sig and R-facs in my outer bin looks hopeful:

 Shell Lower Upper Average      Average     Norm. Linear Square
 limit    Angstrom       I   error   stat. Chi**2  R-fac  R-fac
      20.00   6.40  6165.8   188.1    66.7  1.160  0.038  0.050
       6.40   5.11  3175.2   114.7    67.1  1.056  0.052  0.056
       5.11   4.47  3479.6   139.1    88.4  1.187  0.057  0.087
       4.47   4.06  3006.3   187.6   106.4  0.793  0.070  0.065
       4.06   3.78  2029.3   153.7   107.1  1.038  0.105  0.101
       3.78   3.55  1525.0   148.2   118.3  1.103  0.140  0.116
       3.55   3.38  1241.7   159.4   137.2  1.234  0.160  0.121
       3.38   3.23  1119.2   175.1   155.8  1.151  0.136  0.087
       3.23   3.11   898.8   180.7   166.4  1.147  0.144  0.097
       3.11   3.00   429.6   163.0   158.9  1.183  0.314  0.253
  All reflections   2503.2   159.9   112.0  1.086  0.075  0.069


But my completeness in the outer bins is disasterous:

     Shell            I/Sigma in resolution shells:
  Lower Upper      % of of reflections with I / Sigma less than
  limit limit     0     1     2     3     5    10    20   >20  total
  20.00  6.40   0.6   1.1   1.8   2.5   3.8   7.5  19.1  74.8   93.9
   6.40  5.11   0.9   2.4   3.6   5.2   8.3  16.0  34.2  60.8   95.0
   5.11  4.47   1.5   3.1   4.7   6.3   9.9  18.4  38.8  56.8   95.6
   4.47  4.06   1.7   3.5   5.9   8.5  12.9  28.2  65.9  30.2   96.1
   4.06  3.78   2.5   5.9   9.8  14.4  23.1  43.7  77.1  19.3   96.4
   3.78  3.55   1.8   6.0  12.3  19.5  32.6  58.0  85.8  10.8   96.5
   3.55  3.38   3.5   9.4  18.9  29.7  45.7  69.7  86.9   7.4   94.2
   3.38  3.23   5.4  15.6  27.9  37.7  52.0  66.4  76.4   5.9   82.3
   3.23  3.11   7.1  15.8  25.8  34.4  44.0  52.5  57.8   4.4   62.2
   3.11  3.00   6.2  14.6  22.6  27.9  33.6  38.8  41.7   0.9   42.6
 All hkl        3.1   7.7  13.3  18.5  26.5  39.8  58.2  27.3   85.5

It seems like scalepack is tossing reflections. Is there a reason why? I
picked these resolution limits by inspecting as denzo integrated. There did
not appear to be a great number of reflections tossed during integration.
This appears to be happening during scaling, so I don't believe it is
overlap. Since I used denzo_3d, the fact that I have many partials (1.0
degree oscillations) should not hurt, should it? Eg.:

 type     good   intns   weak overlap  backgr others  total outside    tail
                  ovfl                   prob
 partials  461       0   2142       8       3     28   2642       1       0
 whole      48       0    187       0       1      0    236       0
 total     509       0   2329       8       4     28   2878       1

Scalepack seems to do a fine job with the lower resolution bins where there
are only partials also. I am not sure where the reflections went because the
reject file only has 429 measurements tossed (anomalous was not used). So my
questions are

1. what is denzo/scalepack doing here?
2. will mosflm (which I have yet to learn) handle this situation better?

I will appreciate any help.

James