User manual

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Use the Calibration Statistics icon to
display a table of calibration statistics in the
Image Window. This table of consistency
values determined from the measured
calibration doses and the fitted values and
helps in selecting the best fitting function for the data points. Lower values in the table
signify a better fit. In most cases with doses <500 cGy, the best fitting function is the
rational (linear) function. For a higher dose ranges, e.g. 0-10 Gy the color rational linear
function is often preferred.
The fitting functions and coefficients are expressed as a response, X(D), which is a
function of dose D and the inverse dose as a function of response where response is
expressed as %, i.e. the16-bit value/65535, with dose given in cGy. Click the icon
under the calibration equation to copy and paste a table of the coefficients for all color
channels. To show the OneScan Protocol, go to Program Files/Ashland Advanced
Materials/FilmQAPro/Images/Example EBT3
Rapid Arc and load the file Dose Film
0__313_0.tif. Now highlight the fiducial marks
(indicated by the arrows in the figure) delineating
the axes of the treatment system and the
isocenter. They are the small black marks close
to the center of each edge of the film and
correspond to the position of the cross hairs in
the light field when the film was exposed. Click
on the icon for the “Fiducial management tool”
and use the “General fiducial point”. Since the
fiducial marks are near the centers of the sides
of the Dose film the software “senses” whether a
particular point is fitted in a vertical or horizontal
direction.