the big thanks go to Werner Mausshardt from Bruker Germany, his
prompt (6am!) answer explain the ratio between saved/exported
and displayed intensities. Also to Andrew Gibbs from Bruker UK.
And the complains to Bruker for the (unless someone proves I'm
wrong) lack of information about this issue in the program manual.
The only mention of the 'NC_proc' parameter is in a paragraph dealing
with post-FFT processing of nD spectra, but it is not mentioned
when describing the file '1r' and/or the JCAMP-DX export files.
> From Werner.Mausshardt@bruker.de Tue May 5 09:52:25 1998
>
> Miquel E Cabanas reported
>
> > 3. funny enough (not really), the ratio between intensities reported on-
> > screen and those in the '1r' file gives some interesting values
> > (see the last column)
>
> with a power of 2 ratio.
>
> XWIN-NMR data are stored on disk as 32 bit integer values. To achieve
> best accuracy, XWIN-NMR double precision processing shifts data to
> exploit the full 32 bit range when converting data ot integer. The
> shift number is documented in the processing status parameter NC_proc,
> where positive values count the number of right shifts and negative
> values count the number of left shifts.
> XWIN-NMR internal operations always consider this scaling factor.
> For raw data (fids and ser files) the scaling factor is documented
> in the aquisition status parameter NC.
> 3rd party programs comparing different XWIN-NMR data sets must also
> consider these scaling factors.
Miquel
Miquel E Cabanas ---------------------------------------------------
SeRMN & BBM - Universitat Autonoma de Barcelona, Catalunya - Spain
MRUI url ------- http://www.mrui.uab.es/mrui
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