International
Tables for
Crystallography
Volume F
Crystallography of biological macromolecules
Edited by M. G. Rossmann and E. Arnold

International Tables for Crystallography (2006). Vol. F. ch. 11.2, p. 216   | 1 | 2 |

Section 11.2.6.7.1. Incompletely resolved spots

A. G. W. Lesliea*

aMRC Laboratory of Molecular Biology, Hills Road, Cambridge CB2 2QH, England
Correspondence e-mail: andrew@mrc-lmb.cam.ac.uk

11.2.6.7.1. Incompletely resolved spots

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If adjacent spots are not fully resolved, there will be a systematic error in the integrated intensity which will be largest for weak spots that are adjacent to very strong spots. However, the profile-fitted intensity will be affected less than the summation integration intensity, because the peripheral pixels (where the influence of neighbouring spots is greatest) are down-weighted relative to the central pixels (where the neighbours will have least influence).

Further steps can be taken to minimize the errors caused by overlapping spots. Firstly, when forming the standard profiles, reflections are only included if they are significantly stronger than their nearest neighbours. This will minimize the errors in the standard profiles. Secondly, when evaluating the profile-fitted intensity of a particular reflection, pixels can be omitted if they are adjacent to a pixel that is part of a neighbouring spot (rather than having to be part of that spot).








































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