I.R.I.S. Readiris Corporate 12 for Mac User Guide - Manual (Page 37)

Readiris TM Corporate 12 – User Guide
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(Binarized image. The default binarization settings yield a black
image)
(The lightened image yields satisfactory recognition results)
Example 2: darken an image when the text is so light it doesn't show
up in the binarized image.
(Color image)
(Binarized image. The default brightness settings yield fragmented
characters)
(The darkened image yields satisfactory recognition results)