Re: [ccp4bb] xprep vs shelxc
xprep is free to academics. Since your signature says you work at the University of Helsinki, you would only need to send an informal email to bruker (you could try their contact form http://www.bruker-axs.com/contact.html?L=http%3A%2F%2Fhome.arcor.de%2Fjohnwayne92%2Finc.php ) in order to receive a binary. You do have to repeat this every year, but I think this is a bearable burden. As far as the differences between shelxc and xprep are concerned: shelxc is meant to be a non-interactive basic version of xprep so that it could be called from other programs. It's data preparation should be the same as in xprep and if it really did worse than xprep, I am sure that the improvement from xprep would find its way into shelxc in very little time. We use hkl2map (from Thomas Schneider) routinely for phasing purposes, and since hkl2map calls shelxc rather than xprep, I cannot confirm that xprep prepares the data in a better way than shelxc. Sincerely, Tim -- Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A On Wed, 13 Feb 2008, Tommi Kajander wrote: Dear All, A very simple stupid question: is it worth while getting xprep instead of shelxc to do the same job? i realize xprep does a lot of other things, but also seem to get the idea from some places that it does a better job than shelxc at preparing data from shelxd, or is there any difference (getting xprep will cost some money so i would like to know where the difference lies if there is any significant difference??) Thanks for advice, Tommi -- Tommi Kajander, Ph.D. Macromolecular X-ray Crystallography Research Program in Structural Biology and Biophysics Institute of Biotechnology P.O. Box 65 (Street address: Viikinkaari 1, 4th floor) University of Helsinki FIN-00014 Helsinki, Finland Tel. +358-9-191 58903 Fax +358-9-191 59940
Re: [ccp4bb] xprep vs shelxc
Hi Tim, Unfortunately your statement is not true. The XPREP program was written by George Sheldrick over many years and it is proprietary software distributed by Bruker AXS. We unbundled it from our complete SHELXTL structure solution and refinement package, specifically also to serve macromolecular crystallography groups such as those reading this bulletin board. We have a demo version, which groups can try out, academics or industrials, which expires by the end of each year. Anyone can request a demo version by sending an email to [EMAIL PROTECTED] If all is well, you should get this demo version once and not more. If you did get it more then once, Tim, we did not do our administration right and you were lucky, or it may be because you have changed labs every year. If people find the software useful they can buy a perpetual license from Bruker AXS for a moderate price. Alternatively they can buy an X-ray diffraction system and get the software for free. As far as the differences between SHELXC and XPREP: On the SHELX website it says: SHELXC is much less versatile than the Bruker AXS XPREP program for macromolecular phasing, but if you are sure of the space group and there are no problems with the indexing or twinning and the f and f parts of the scattering factors do not need to be refined, SHELXC should be adequate. SHELXC can read either HKL2000 .sca files or SHELX .hkl files. Xprep has many more possibilities then SHELXC: It can search for higher symmetry in datasets, determine space groups, it has tests for merohedral twinning, reciprocal lattice displays, unit cell transformations and can calculate Self-Rotation functions. The results for anomalous phasing from XPREP look better then those from SHELXC at first sight, but I have not done a rigorous study into this matter. Best wishes, Bram -- Bram Schierbeek Application Scientist Structural Biology Solutions Bruker AXS BV Oostsingel 209,P.O.Box 811 2600 AV Delft, the Netherlands T: +31 (0)152 152 508 F: +31 (0)152 152 599 E: [EMAIL PROTECTED] W: www.bruker-axs.com Tim Gruene wrote: xprep is free to academics. Since your signature says you work at the University of Helsinki, you would only need to send an informal email to bruker (you could try their contact form http://www.bruker-axs.com/contact.html?L=http%3A%2F%2Fhome.arcor.de%2Fjohnwayne92%2Finc.php ) in order to receive a binary. You do have to repeat this every year, but I think this is a bearable burden. As far as the differences between shelxc and xprep are concerned: shelxc is meant to be a non-interactive basic version of xprep so that it could be called from other programs. It's data preparation should be the same as in xprep and if it really did worse than xprep, I am sure that the improvement from xprep would find its way into shelxc in very little time. We use hkl2map (from Thomas Schneider) routinely for phasing purposes, and since hkl2map calls shelxc rather than xprep, I cannot confirm that xprep prepares the data in a better way than shelxc. Sincerely, Tim -- Tim Gruene Institut fuer anorganische Chemie Tammannstr. 4 D-37077 Goettingen GPG Key ID = A46BEE1A On Wed, 13 Feb 2008, Tommi Kajander wrote: Dear All, A very simple stupid question: is it worth while getting xprep instead of shelxc to do the same job? i realize xprep does a lot of other things, but also seem to get the idea from some places that it does a better job than shelxc at preparing data from shelxd, or is there any difference (getting xprep will cost some money so i would like to know where the difference lies if there is any significant difference??) Thanks for advice, Tommi -- Tommi Kajander, Ph.D. Macromolecular X-ray Crystallography Research Program in Structural Biology and Biophysics Institute of Biotechnology P.O. Box 65 (Street address: Viikinkaari 1, 4th floor) University of Helsinki FIN-00014 Helsinki, Finland Tel. +358-9-191 58903 Fax +358-9-191 59940
Re: [ccp4bb] xprep vs shelxc
XPREP and SHELXC use different algorithms and sometime one of them will give better results than the other. In particular for MAD data, XPREP takes the actual f' and f values into account and can refine them if you have at least three wavelengths, whereas SHELXC uses standard values and scales them as required. XPREP does lots of other things that can be useful for experimental phasing, e.g. space group determination, merging data, twinning detection and anisotropic scaling. George Prof. George M. Sheldrick FRS Dept. Structural Chemistry, University of Goettingen, Tammannstr. 4, D37077 Goettingen, Germany Tel. +49-551-39-3021 or -3068 Fax. +49-551-39-2582 On Wed, 13 Feb 2008, Tommi Kajander wrote: Dear All, A very simple stupid question: is it worth while getting xprep instead of shelxc to do the same job? i realize xprep does a lot of other things, but also seem to get the idea from some places that it does a better job than shelxc at preparing data from shelxd, or is there any difference (getting xprep will cost some money so i would like to know where the difference lies if there is any significant difference??) Thanks for advice, Tommi -- Tommi Kajander, Ph.D. Macromolecular X-ray Crystallography Research Program in Structural Biology and Biophysics Institute of Biotechnology P.O. Box 65 (Street address: Viikinkaari 1, 4th floor) University of Helsinki FIN-00014 Helsinki, Finland Tel. +358-9-191 58903 Fax +358-9-191 59940
[ccp4bb] xprep vs shelxc
Dear All, A very simple stupid question: is it worth while getting xprep instead of shelxc to do the same job? i realize xprep does a lot of other things, but also seem to get the idea from some places that it does a better job than shelxc at preparing data from shelxd, or is there any difference (getting xprep will cost some money so i would like to know where the difference lies if there is any significant difference??) Thanks for advice, Tommi -- Tommi Kajander, Ph.D. Macromolecular X-ray Crystallography Research Program in Structural Biology and Biophysics Institute of Biotechnology P.O. Box 65 (Street address: Viikinkaari 1, 4th floor) University of Helsinki FIN-00014 Helsinki, Finland Tel. +358-9-191 58903 Fax +358-9-191 59940
