RANTAN

["Kostrewa, Dirk {PRPC~Basel}" <DIRK.KOSTREWA@roche.com>]

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Dear CCP4 users,

I would like to try RANTAN for the determination of heavy atom positions
from a derivative data set. However, from the documentation (CCP4 v3.5.1) it
is not quite clear to me how to do it. Here are my questions to those of you
who have successfully applied RANTAN:

(1) which coefficients do you take as the source for calculating E-values:
FPH or |FPH-FP| ?
(2) does RANTAN also work with origin-removed (E**2-1) coefficients ?
(3) how do you convert the results to heavy atom positions ? do you
calculate an electron density map with Fourier coefficients
WT1*E*exp(i*PHI1) or with coefficients WT1*|FPH-FP|*exp(i*PHI1) and run
PEAKMAX then, or is done completely different ?

Any hints are welcome!

Kind regards,
Dirk.

*******************************************************
* Dirk Kostrewa                phone: +41-61-688-7750 *
* F.Hoffmann-La Roche Ltd.       fax: +41-61-688-7408 *
* PRPC-S B65/R312                                     *
* CH-4070 Basel, Switzerland                          *
* e-mail: dirk.kostrewa@roche.com                     *
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