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Finding out ORGX ORGY: Difference between revisions
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# 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. (If XDS-Viewer does not know the format, it will ask for NX, NY, and the size of the header. The latter is usually <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. (If XDS-Viewer does not know the format, it will ask for NX, NY, and the size of the header. The latter is usually <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 | # 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 when going from MOSFLM units to XDS units). 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. | ||
# use the Unix command line tools to look at the header of the frame. E.g. "strings <frame-name>|more" would should you the (hopefully correct) information stored in the header, like wavelength, delta-phi, X and Y beamcentre and so on. | # use the Unix command line tools to look at the header of the frame. E.g. "strings <frame-name>|more" would should you the (hopefully correct) information stored in the header, like wavelength, delta-phi, X and Y beamcentre and so on. | ||