I should add that inspecting the average three-dimensional profiles in
INTEGRATE.LP could give you an indication if you have overlaps or not.
The profiles look like slices through a 3D  unimodal gaussian. If you
have overlaps it will be revealed by bi-/multi-modal features. However,
these are average profiles so a small number of overlaps may not be
apparent. 

/Michel


On Wed, 2008-02-20 at 14:54 -0800, Engin Ozkan wrote:

> Hi everyone,
> 
> I have been recently relying on XDS quite a bit, but at the same time 
> worrying about how XDS treats overlaps.  We had one dataset that both 
> HKL2000 and Mosflm would show to have severe overlaps, as expected due 
> to unit cell parameters and the unfortunate crystal orientation in the 
> loop. We always ended up with completeness percentages in the 70's.
> 
> XDS can find the same lattice, index and scale the data, but yields a 
> 100% complete mtz (and a nice structure). Without the HKL/Mosflm-like 
> GUI, it is difficult to assess the fate of the overlapped observations 
> in XDS. What I could see with VIEW was that some observations were being 
> divided into several ovals, probably different reflections, but I'm not 
> very certain.
> 
> So, the basic question is, how does XDS treat overlaps?  I could not 
> find in the documentation an answer to this question; the single mention 
> of overlaps I could find tells me that XDS can recognize overlaps, but 
> does not tell me if it rejects them, or divvies them up into separate 
> reflections, and if that is the case, how does it divide them, and how 
> reliable is that? Depending on how it divides the overlaps, could that 
> affect commonly-used intensity stats and distributions?
> 
> Thanks,
> 
> Engin

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