Hi Niu -
In HKL2000, you should first get an indexing solution with the 40 A
axis, as you have done previously. Then go to the tab of the GUI
labeled "Macros". In the bottom row, "Immediate Execution", you enter
the following:
unit cell a b c alpha beta gamma
where you replace the words after "unit cell" with the desired unit cell
dimensions, including your 20 A axis. (Make sure you use exactly half
of the previous cell dimension.) Then hit "Run Macro". If it works
correctly, you should see every other predicted spot disappear in your
XdisplayF window. Now look to see if those predicted spots should have
been removed or not! Use the zoom window to help with this.
You should be able to refine the new cell parameters normally.
Hope that helps,
Matt
On 11/18/13 5:03 PM, Niu Tou wrote:
Dear Andrew,
As previously I posted a MR case which has a significant 95% off
origin peak, some experts suggested to reprocess the data with cutting
one axis to half, from 40A to 20A. I tried HKL2000 and XDS, none of
them is willing to give a solution with 20A, even I specify it in XDS
script. So I wonder is there any way to force this work to be done.
Thanks!
Best,
Niu
On Mon, Nov 18, 2013 at 4:56 PM, Andrew Leslie
<and...@mrc-lmb.cam.ac.uk <mailto:and...@mrc-lmb.cam.ac.uk>> wrote:
Dear Niu,
It depends on which part of processing you are
referring to, i.e. the indexing step or the integration step. In
MOSFLM there is no way to enforce cell dimensions during indexing,
but providing there is an indexing solution that has cell
dimensions close to the ones you want, you can enforce a
(slightly) different set of cell dimensions during the integration
step. Normally other refined parameters will ensure that you still
get a good prediction of spot positions.
I suspect that this can be done in other programs too.
Without knowing why you want to do this, I cannot comment on
whether this is the best procedure to follow.
Best wishes,
Andrew
On 18 Nov 2013, at 21:48, Niu Tou <niutou2...@gmail.com
<mailto:niutou2...@gmail.com>> wrote:
> Dear All,
>
> Does any one know how to strictly fix the cell dimensions during
data processing? In HKL2000 there is only a keyword to define the
longest vector. In XDS there is a option to input cell parameters,
but sometimes the program would not follow the input values
> and switch back to the one it thinks best. Any suggestions will
be appreciated. Thanks!
>
> Best,
> Niu
--
Matthew Franklin, Ph. D.
Senior Scientist
New York Structural Biology Center
89 Convent Avenue, New York, NY 10027
(212) 939-0660 ext. 9374
