Re: [ccp4bb]: MOSFLM, XDS, DENZO - conversion of crystal missetting angles ?

[Phraenquex VD <loretta@scripps.edu>]

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> Is there a simple way to convert the crystal missetting angles as given in
> xds to the conventions used in Mosflm or Denzo ? I would like to try
> integrating the data in mosflm and in denzo as well.
> 
> The images are weak, one of the axes is almost perfectly aligned with the
> spindle axis and, as written, the resolution poor. XDS probably succeeds
> because it can use more frames than mosflm (6.1) or denzo.

Mosflm?  In my experience, mosflm can use a rather large number of
frames... I think I once went as far as 20.  When I index, I use two
images at least 45 degrees apart as a matter of course, it tends to save a
lot of agony. 

Weak images, too, often don't seem to bother it, I've successfully indexed
images using just 10 spots, all worse than 4A.

The only thing that does seem to matter is the beam position -- and that
applies to all programs I've used.  The old mosflm indexing algorithm (the
one you get when you say "no" when asked whether to use DPS), that one
seems a bit more robust about the beam centre, but then you need strong
images and certainly include spots from several images widely separated in
phi. 

Also be careful about that, the x and y convention is switched between
some programs.  I can never remember which it is, but I think where mosflm
uses (x,y), denzo and d*trek use (y,x).  Or something like that, try both. 

good luck
phx.