On Thu, 2007-05-03 at 19:51 -0300, Alejandro Buschiazzo wrote:
> Dear ccp4bb users,
>
> I have a question that concerns a problem with data collection (not
> directly related to CCP4). It might be a really stupid mistake I'm making...
>
> I'm attaching a diffraction frame where, as you can easily see, there
> is an annoying shadow...
I agree with the others that the shadow could indeed be caused by your
pin, and is not a problem as the software commonly in use corrects for
local background. If you want to reduce the shadow, you could reduce the
air scatter in between the collimator and the crystal. A shorter
distance would mean less air scatter, but of course you don't want your
collimator to impinge on your cryo stream. Possibly details of the
collimator could be contributing, I don't know anything about hte design
or quality of collimator you are using. Another way to reduce air
scatter would be to reduce the air by putting the experiment in a helium
box.
--
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With the single exception of Cornell, there is not a college in the
United States where truth has ever been a welcome guest - R.G. Ingersoll
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David J. Schuller
modern man in a post-modern world
MacCHESS, Cornell University
[EMAIL PROTECTED]
