Thanks - indeed I was simply unaware that the mosaicity is always
reported as zero when using (auto)xds. So I guess since only two
datasets also behave badly in mosflm, and both have bad multiple
latticitis, my questions are answered.
Thanks,
Ed.
On Fri, 2012-05-25 at 16:31 +0100, Graeme Winter wrote:
> Hi Ed,
>
> If you use XDS for integration then all of the reflections are full
> (they are summed by the program during the integration), so there are
> no partials from which to determine an estimate of the mosaic spread
> in Scala.
>
> Mosflm 0 mosaic spread is a different issue, but has been much
> improved in the latest versions of the program.
>
> Best wishes,
>
> Graeme
>
> On 25 May 2012 16:12, Ed Pozharski <[log in to unmask]> wrote:
> > I should do more digging, but I hope maybe there is a simple explanation
> > and someone has seen this before. On some datasets (collected at SSRL)
> > I get SCALA reporting average mosaicity of 0.0. This probably happens
> > at the integration stage, and for this whole set of datasets *always*
> > happens when I use the autoxds scripts. When I go with mosflm/scala, it
> > still happens for some, but not all datasets. I can process those that
> > fail mosflm using denzo/scalepack, but it takes a bit of tinkering with
> > parameters (diffraction is admittedly messy).
> >
> > Interestingly, it seems that at least in some cases all the other SCALA
> > statistics are perfectly fine. I haven't checked yet how these will
> > behave in refinement, but I suspect it will look OK too.
> >
> > I have found this by googling
> >
> > [log in to unmask]" target="_blank">http:[log in to unmask]
> >
> > but it's from 2005 and I wonder if things changed since. Andrew
> > mentions the multiple close lattices as one of the possible reasons, and
> > it is indeed fairly common for these datasets.
> >
> > I cannot find anything in SCALA manual about mosaicity refinement, so I
> > assume that scala (unlike scalepack) does not do that. So if I am to
> > overcome the zero mosaicity issue by fixing it at mosflm stage, how
> > important it is to get it close to the actual value? Or is it enough to
> > just keep it sufficiently high to prevent rejections of legit spots?
> > And, if I may ask one last question, is there a way to fix mosaicity in
> > imosflm gui (I can *fix* it, but doesn't seem to be possible to choose a
> > specific value).
> >
> > Cheers,
> >
> > Ed.
> >
> > --
> > After much deep and profound brain things inside my head,
> > I have decided to thank you for bringing peace to our home.
> > Julian, King of Lemurs
--
Edwin Pozharski, PhD, Assistant Professor
University of Maryland, Baltimore
----------------------------------------------
When the Way is forgotten duty and justice appear;
Then knowledge and wisdom are born along with hypocrisy.
When harmonious relationships dissolve then respect and devotion arise;
When a nation falls to chaos then loyalty and patriotism are born.
------------------------------ / Lao Tse /
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