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Just to add my little contribution: high resolution limit does not seem to
be an easy to measure quantity. This is what I found most appropriate:
-integrate first using all the surface of the detector;
-then have a look at the Rsym curve as a function of the resolution;
-this curve (from low res to high res) goes down then gradually rises and
at some stage there is a sharp rise (basically it becomes vertical or
nearly so);
-I try to estimate the resolution at which this sharp rise starts and I
process again, this time giving that figure as a high resolution limit.
Sometimes this means that the Rsym in the high resolution shell will be
lower than 50%, sometimes higher than 50%. IoSI seems to be always
slightly higher than 1.0 in the high resolution shell (thin slices).
I for one will ask myself how the high resolution limit was obtained when
acting as a reviewer. It is not a question of wondering if it is "poor" or
"good" crystallography, just to know if the last 0.1 A are data or only
indices. This is difficult to know from the tables provided. I have
seen real cases where Rsym ca 45% were only indices, and cases where Rsym
> 55% were real useful data. I guess that the indicator is "is the map
computed at given resolution - 0.1 A as good as the map computed at given
resolution". Unfortunately this information is not made available to
reviewers.
Well that was my thought of the day.
Fred.
--
s-mail: F.M.D. Vellieux (B.Sc., Ph.D.)
Institut de Biologie Structurale J.-P. Ebel CEA CNRS UJF
41 rue Jules Horowitz
38027 Grenoble Cedex 01
France
Tel: (+33) (0) 438789605
Fax: (+33) (0) 438785494
e-mail: [EMAIL PROTECTED]
