Finding out ORGX ORGY: Difference between revisions

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There are different possibilities to find out where the direct beam would hit the detector:
There are different possibilities to find out where the direct beam would hit the detector:


# visualize BKGINIT.cbf (from INIT), or FRAME.cbf (from COLSPOT) with [[XDS-Viewer]], and click (left-mouse) into the middle of the beamstop shadow (or the attenuated direct beam itself, if it is recorded). Use the pixel coordinates displayed by [[XDS-Viewer]] as ORGX ORGY (in principle you should add 1 to both numbers, because for XDS-Viewer the pixels go from 0 to NX-1 whereas for XDS they go from 1 to NX).<br />Instead of these files written by XDS, one could directly use a measured frame. However this requires that one enters NX, NY, and the size of the header (which usually is <size of frame in bytes>, minus 2*NX*NY).
# visualize BKGINIT.cbf (from [[INIT]]), or FRAME.cbf (from [[COLSPOT]]) with [[XDS-Viewer]], and click (left-mouse) into the middle of the beamstop shadow (or the attenuated direct beam itself, if it is recorded). Use the pixel coordinates displayed by [[XDS-Viewer]] as ORGX ORGY (in principle you should add 1 to both numbers, because for XDS-Viewer the pixels go from 0 to NX-1 whereas for XDS they go from 1 to NX).<br />Instead of these files written by XDS, one could directly use a measured frame. However this requires that one enters NX, NY, and the size of the header (which usually is <size of frame in bytes>, minus 2*NX*NY).
# use adxv for visualization. Otherwise the same as with XDS-Viewer. (1.9.7beta version works for the PILATUS detector at SLS)
# use [[adxv]] for visualization. Otherwise the same as with XDS-Viewer. (1.9.7beta version works for the PILATUS detector at SLS)
# use MOSFLM for visualization. It prints out X BEAM and Y BEAM from the frame header, and you may click on the hypothetical direct beam position. However, ''x and y are swapped in MOSFLM when compared to XDS'', and the coordinates are in mm, not in pixels (so one has to divide by QX). Sometimes the X BEAM and Y BEAM from the header are not reliable.
# use MOSFLM for visualization. It prints out X BEAM and Y BEAM from the frame header, and you may click on the hypothetical direct beam position. However, ''x and y are swapped in MOSFLM when compared to XDS'', and the coordinates are in mm, not in pixels (so one has to divide by QX). Sometimes the X BEAM and Y BEAM from the header are not reliable.
# use ice rings to find out (in [[XDS-Viewer]], and with paper and pencil) where the direct beam would be. This should be rather accurate but may be tedious.
# use ice rings to find out (in [[XDS-Viewer]], and with paper and pencil) where the direct beam would be. This should be rather accurate but may be tedious.
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