# Determine a Foreground Threshold

An OCRMax tool allows you to specify a fractional percentage for the threshold grey value used to differentiate potential character pixels from background pixels after the image has undergone image normalization.

The default value of 0.5 produces a threshold grey value of 128, the halfway point of grey values between 0 and 255. Increasing or decreasing this parameter has the corresponding effect on the threshold grey value.

Use the ForegroundThresholdFrac property to specify a different fractional percentage.

You may need to experiment to determine the best value for your vision application, but be aware that the 0.5 default value works well for a majority of test cases.