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<div>The primary beam may not hit the detector, not even the extended detector plane. So no, the local origin sits at the first pixel.
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Cheers <br>
Tobias <br>
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<div>Data Management Group<br>
European Spallation Source, Lund, Sweden<br>
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<div style="border:none; padding:3.0pt 0cm 0cm 0cm"><span style="font-size:11.0pt; font-family:'Calibri','sans-serif'"><b>From:</b> Eugen Wintersberger <eugen.wintersberger@desy.de><br>
<b>Sent:</b> 28 Jul 2017 14:55<br>
<b>To:</b> nexus-committee@nexusformat.org<br>
<b>Subject:</b> [NeXus-committee] A very stupid question<br>
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<div>Hi folks, <br>
I know this sounds rather stupid but: am I right if I assume that the beam center (the location where the
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primary beam hits the detector) is the origin of the detectors local coordinate frame?<br>
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Background: I am actually cleaning up my DESY internal Nexus documents including use cases for
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NXtransformation and NXdetector (for different detector configurations) and while doing this I realized that I am not
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sure about the definition of the origin of the detector local coordinate frame. <br>
I already have some nice results using NXtransformation for q-space conversion and maybe we could use
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these documents, once they are finished, as cookbooks for Nexus users. <br>
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regards<br>
Eugen<br>
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<td>-- <br>
Dr. Eugen Wintersberger <br>
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FS-EC <br>
DESY <br>
Notkestr. 85 <br>
D-22607 Hamburg <br>
Germany <br>
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