The Islandora OCR module integrates Tesseract into the Islandora Paged Content module. It allows for creation of OCR and HOCR derivatives that can be appended to a page as a datastream. Check the instructions for the OCR-compatible module you wish to use for specifics on how to create OCR derivatives.
Configuration options for the Islandora OCR module can be found at http://path.to.your.site/admin/islandora/ocr, and include the following options:
It is recommended to check the Tesseract page for more information on these options.