User manual
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Point the cursor and click on each fiducial mark to add highlight marks. The fiducial
fitting senses the center of the highlight marks, not the marks scribed on the film. For
precise adjustment click on a highlight, press the Control key and use the keyboard
arrows to move the mark.
When FilmQA
™
Pro has finished calculating the dose map (using multi-channel
dosimetry), select the dose map and draw areas of interest at the center of the two
reference strips. Click the “Statistics” tab to show a table of dose values. Look at the
values for Frames 1 and 2. In Frame 1, they are close to zero in each color channel; but
for Frame 2, the values for the exposed reference film are all close to 310 cGy when
they should be 313 cGy. The differences between the measured and actual values are
the result of scan-to-scan variability – either from the scanner itself, or because the
reference/application films were scanned at a different ambient temperature than the
calibration films. If you stopped at this point you’d have accepted a 1% offset in your
dose map.