I know OCR software elsewhere often recommends TIFFs for the OCR process. Is the same true for DTPoffice?
The reason I asked, is I just noticed that JSTOR offers articles in TIFF format and PDF format, and the reason they say they provide TIFF is specifically for OCR.
I usually prefer working from PDFs that have been scanned to a resolution of at least 300 ppi.
I’m not certain, but perhaps JSTOR provides TIFF files that have a higher resolution than their PDF files.
those are some strong pdf’s Bill, 300 pounds per square inch 
I prefer PDF’s as well, but if it meant more accurate OCR, I’d figure out a workflow for TIFF’s.