Filter
Top Products
m
ar345 Program Manual 2 2
_
____________________________________________________________________________________
_
3
.14 X−ray Setup
When producing images during data collection many parameters concerning the curren
t
experiment are automatically written into the output image headers, so this information ca
n
be retrieved later on. This is most relevant for parameters like the distance and th
e
goniometer positions. It might, however, be useful to add also some information about th
e
state of the X−ray source. Unfortunately, the program mar345 does not have knowledg
e
about the generator and collimator settings, so this information must be entered manuall
y.
For this purpose, open the mar345−X−ray Setup window. This window can be popped u
p
manually from the main window menubar or by pressing the F3 key. All information give
n
here is really not essential but it may help later on to track down problems during dat
a
processing.
The center of diffraction is supposed to be a physical constant (for one data set) and is val
id
for all scan modes, regardless if working at 0.15 or 0.10 mm pixelsize. This is why the cente
r
should not be entered in absolute pixels or millimeters referring to an origin in the lower le
ft
corner but as a deviation from the center of the image plate. These values should be given
in
mm, not in pixels, and can become negative. Negative x deviation means that the center o
f
diffraction is left of the IP−center. A negative y deviation would be underneath the IP−center
.