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The equation of the model was coded into a computer program
using Microsoft Visual Basic. The program incorporated flash output
level, flash zoom, flash distance to subject, ISO rating, aperture
f-number, shutter speed, and the flash clipping effect determined by the
model to compute correct flash exposure. The photographer can use the
program to determine settings for correct exposure when using flash with
shutter speeds higher than 1/250 second.
The computer program was tested by taking a total of 28 trial shots of
the grey card with a Canon G9 camera under
various conditions. The conditions were inputted into the computer
program to determine the settings to be used for correct exposure. The
trial shots were taken with the computed settings. Statistical analysis
performed on the data from the trial shots for the prediction errors
resulted in an average of -0.06 stops with a standard deviation of 0.13
stops and a 99% confidence interval of -0.13 to -0.00 stops.
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