User manual

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The Delta Map Tab shows the passing rates (gamma
analysis in the example) for the all three color channels
below the chart. The chart in the window displays the
pass/fail data for the red, green and blue color channels
in map form. Pixels passing the gamma test in all three
channels are dispayed in black. If a pixel fails the
gamma test for a particular channel it is displayed in that
color or mix of colors. White indicates areas where all
three channels fail the gamma test.
Icons along the left hand border of the window give
access to tools available in the Image Window and
described in that Section. The Map can be exported to other applications either as an
image file or a CSV table. Use the Comparison Map Selector icon to choose
between displays of analytic data from gamma , DTA, or dose difference maps.
The Projection Map is critical to the proper
calculation of the dose distribution comparison
functions. The dose map and treatment plan cannot
be compared without placing them in the same spatial
domain. Because film is usually scanned at ≥72 dpi or
more, the spatial resolution of the dose map is almost
always much greater than the treatment plan. This
means there are >1 measured pixels for every plan
pixel. To prevent gross overestimation of the passing
rates the plan and measured dose maps must be put
on the same basis for evaluation and comparison.
That is, the measured dose map must be projected to
the grid of the plan. To do this FilmQA
™
Pro