We have developed a new reflection data integration method, Eval15, that uses profile prediction. It has the potential of integrating complicated reflection data, such as arise from anisotropic crystal shape, anisotropic mosaicity, ????? splitting, overlap due to twin lattices. At the same time Eval15 has the advantage of accurate integration of weak intensities as a result of profile fitting. It is a follow-up of Eval14 [1], a reflection box-integration method that uses calculated boundaries based on a few physical crystal and instrument parameters. Eval14 is well established for the integration of small molecule data and is especially useful in problematic cases. Weak reflections, however, are not integrated as accurately as it is done by profile fitting methods. This is cumbersome for protein data where the structure determination relies on the accuracy of weak data.
The principle of general impact used by Eval14 to predict the reflection boundaries are now used to predict the complete profile of the reflection, that can then be used as a standard profile in a profile fitting algorithm. Every reflection has its own predicted profile that is based on the same physical parameters as in Eval14.
In the present contribution we show the first data integrated by Eval15. For small molecules Eval15 has a comparable quality as Eval14 and for proteins it produces data comparable to the profile learning methods Denzo and Mosflm.
[1] A.J.M.Duisenberg, L.M.J. Kroon-Batenburg and A.M.M. Schreurs (2003). An intensity evaluation method: EVAL-14. J. Appl. Cryst. 36, 220-229.