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Finding out ORGX ORGY: Difference between revisions
→The case of a swung-out detector
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# in the right-angled triangle of crystal, (ORGX,ORGY), and (Xbeam,Ybeam), we can find the distance (ORGX-Xbeam) by taking tan(2theta)*|DETECTOR_DISTANCE|/QX . | # in the right-angled triangle of crystal, (ORGX,ORGY), and (Xbeam,Ybeam), we can find the distance (ORGX-Xbeam) by taking tan(2theta)*|DETECTOR_DISTANCE|/QX . | ||
# now since sin(2theta)~tan(2theta) we can approximate the adjustment by S2T*|DETECTOR_DISTANCE|/QX | # now since sin(2theta)~tan(2theta) we can approximate the adjustment by S2T*|DETECTOR_DISTANCE|/QX | ||
# for large 2theta one obviously has to take the arc sine of S2T, and calculate tan(2theta) from that. | |||
Second method: if you feel you would rather like to find ORGX, ORGY by smart trial-and-error, then you just need to realize that in the output of IDXREF.LP you can check the lines | |||
DETECTOR COORDINATES (PIXELS) OF DIRECT BEAM 361.92 533.30 ! this should agree with XDS-Viewer findings | |||
DETECTOR ORIGIN (PIXELS) AT 512.37 533.63 ! this should agree with specified ORGX, ORGY | |||