You will usually start a project with unmerged data or even images but if you have already merged data then this task will import it into CCP4I2 - converting to the MTZ format if necessary and creating a Reflection data object and also a FreeR data object if FreeR data is available. The task will then run some of the tools usually associated with Data Reduction to provide a report on the quality of the data.


The input to this task requires spacegroup, cell and wavelength - if this information is present in the file it will be read and displayed - otherwise you will have to enter the data. MTZ files may contain multiple sets of reflection data and you will be required to select the set you want to use.

The task will import files in the usual CCP4 MTZ format, mmCIF format (as is usually distributed by the PDB (PDBe, RCSB, PDBj) with a file name of the form xnyzsf.ent) and Scalepack format (usually has entension .sca). The latter two formats are readable files whose first few lines are of the form:

Merged reflection data file formats

_audit.revision_id    1_0
_audit.creation_date  2014-04-16
_audit.update_record   'Initial release' 
_cell.entry_id      4oog 
_cell.length_a      157.9720 
_cell.length_b      183.8040 
_cell.length_c      61.2890 
1 1 1    0    0    2 o  108.900   1.6000 
1 1 1    0    0    4 o   73.900   1.1000 
1 1 1    0    0    6 o   32.700   0.5000 
1 1 1    0    0   10 o   19.100   0.5000 
1 1 1    0    0   12 o   56.300   0.9000 

MMCIF files are very flexible and very variable, beware the same format may contain atomic coordinates rather than reflection data. The file may or may not contain space group, cell and wavelength information.

   108.742    61.679    71.652    90.000    97.151    90.000 c2        
 -50   0   2  3530.5   733.8
 -50   0   3   210.8   357.2
 -50   0   6  1930.8   547.3

This file format contains spacegroup and cell data but not wavelength.

Other formats

CCP4I2 supports the commonly used reflection file formats but there are some others which can be converted to MTZ by the appropriate CCP4 program:
convert2mtzCNS, PHS and SHELX

The report from this job is a sub-set of the report from the Data reduction task.