For me, it means a reflecting-range (as defined by XDS) of 5-10 or more degrees
and spots being visible on at least 5 or more frames (when using 1° frames).
Good crystals (in our hands) have reflection-ranges in the order of 0.5-1.0°.
Of course we trust that the synchrotron where we measure (ESRF, SLS) has a
well-colimated beam with low beam divergence etc. So I guess, my definition
would be high relative to the rotation range.
I hope this answers your question,
Herman
________________________________
From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of
Colin Nave
Sent: Friday, January 28, 2011 3:50 PM
To: [email protected]
Subject: Re: [ccp4bb] Merging data to increase multiplicity
Can people say how "high mosaicity" is defined. High relative to what?
Is it high relative to the rotation range for each image, high relative
to the incident beam divergence, high relative to the (angular) detector
resolution or something else?
Regards
Colin
From: CCP4 bulletin board [mailto:[email protected]] On Behalf Of
[email protected]
Sent: 28 January 2011 14:36
To: [email protected]
Subject: Re: [ccp4bb] Merging data to increase multiplicity
My experience (unpublished) is that XDS works very well for
high-mosaicity crystals due to the 3-dimensional profile fitting. For low
mosaicity crystals, I did not notice much of a difference between different
programs. However, since bad crystals tend to have a high to very high
mosaicity, I fully agree with Jürgens statement.
Best regards,
Herman
________________________________
From: CCP4 bulletin board [mailto:[email protected]] On
Behalf Of Van Den Berg, Bert
Sent: Friday, January 28, 2011 2:38 PM
To: [email protected]
Subject: Re: [ccp4bb] Merging data to increase multiplicity
I have heard this before. I'm wondering though, does anybody
know of a systematic study where different data processing programs are
compared with real-life, non-lysozyme data?
Bert
On 1/28/11 7:58 AM, "Bosch, Juergen" <[email protected]> wrote:
I was a bit reductive with my statement (iPhone....)
The equation below is suppose to read:
If you have bad data, then you need to process with XDS in
order to get the maximum out of your data.
Thanks Tim,
Jürgen
-
Jürgen Bosch
Johns Hopkins Bloomberg School of Public Health
Department of Biochemistry & Molecular Biology
Johns Hopkins Malaria Research Institute
615 North Wolfe Street, W8708
Baltimore, MD 21205
Phone: +1-410-614-4742
Lab: +1-410-614-4894
Fax: +1-410-955-3655
http://web.mac.com/bosch_lab/ <http://web.me.com/bosch_lab/>
On Jan 28, 2011, at 7:44 AM, Tim Gruene wrote:
Dear Jürgen,
is this an assignment operator or an equal sign? For if it's
the latter it could
read that the result of processing data with XDS are bad data,
which is rather
rude and probably not what you meant.
Tim
On Fri, Jan 28, 2011 at 06:55:43AM -0500, Jürgen Bosch wrote:
Bad data = processing with XDS
Jürgen
......................
Jürgen Bosch
Johns Hopkins Bloomberg School of Public Health
Department of Biochemistry & Molecular Biology
Johns Hopkins Malaria Research Institute
615 North Wolfe Street, W8708
Baltimore, MD 21205
Phone: +1-410-614-4742
Lab: +1-410-614-4894
Fax: +1-410-955-3655
http://web.mac.com/bosch_lab/
On Jan 28, 2011, at 6:46, José Trincão <[email protected]>
wrote:
Hello all,
I have been trying to squeeze the most out of a bad data set
(P1, anisotropic, crystals not reproducible). I had very incomplete data due to
high mosaicity and lots of overlaps. The completeness was about 80% overall to
~3A. Yesterday I noticed that I could process the data much better fixing the
mosaicity to 0.5 in imosflm. I got about 95% complete up to 2.5A but with a
multiplicity of 1.7. I tried to integrate the same data fixing the mosaicity at
different values ranging from 0.2 to 0.6 and saw the trend in completeness,
Rmerge and multiplicity.
Now, is there any reason why I should not just merge all these
together and feed them to scala in order to increase multiplicity?
Am I missing something?
Thanks for any comments!
Jose
José Trincão, PhD CQFB@FCT-UNL
2829-516 Caparica, Portugal
"It's very hard to make predictions... especially about the
future" - Niels Bohr
