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Dear Francis,

                        The quick answer is no.  My initial advice  
would be to process the data in the usual way, but treating the images  
starting at "phistart" as one "run" and the images starting at  
"phistart+180" as a different run. This makes a number of assumption  
however:

1. That the images are numbered appropriately to allow you to do this.  
If not you may have to rename them.

2. That the "blocks" of images (ie the number of images collected  
before phi is changed to phi+180 or back again) are small enough that  
one can assume that the scale factors and B factors are varying  
smoothly with no discontinuities within the two runs (phistart and  
phistart+180), so that the smooth scaling in SCALA works correctly. If  
this is not the case, you may have to make each "block" of images a  
separate run in SCALA (but this could have its own problems if there  
are not many images). You must, of course, make sure that the two runs  
(phistart and phistart+180) are indeed recognised as separate runs by  
SCALA, this will depend on the batch numbers assigned to each image.

3. That the goniometry on the beamline is sufficiently stable that  
there are no discontinuities in the phi values when switching between  
phi and phi+180.

4. That the crystal mount is stable enough that there are no  
discontinuities in crystal orientation between different blocks.

These factors will depend on how the data has been collected,but for  
the (relatively few) inverse beam data sets that I have processed  
(where phi was changed to phi+180 after every image), the default  
procedure worked well.

Best wishes,

Andrew



On 2 Feb 2011, at 00:03, Francis E Reyes wrote:

> Hi all
>
> Is there a walkthru/tutorial for processing inverse beam images with  
> imosflm/scala? Googling  a few things didn't get me anywhere.
>
>
> Thanks!
> F
>
> ---------------------------------------------
> Francis E. Reyes M.Sc.
> 215 UCB
> University of Colorado at Boulder
>
> gpg --keyserver pgp.mit.edu --recv-keys 67BA8D5D
>
> 8AE2 F2F4 90F7 9640 28BC  686F 78FD 6669 67BA 8D5D