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Originally Posted by user
I am just trying to find the optimum camera for the job
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You get what you pay for (camera) but the best things in life are free (DIY v-cradle). When you buy a camera after a long research, the next day you learn about a better one.
Some cameras come with a text/document mode. Do not fall for it but just note what are the settings they provide for that mode. E.g. my Casio EX-Z850 uses the following settings: EV Shift +1, white balance Auto, ISO Auto, Sharpness +1, Saturation 0, Contrast +1. Of all these parameters the only one worth considering when shooting a document in automatic mode is EV Shift (exposure compensation), which provides for brighter pictures. The other parameters can be adjusted by software in processing stage (modifying sharpness before OCR is not recommended). With my rather dim lighting setup I usually use EV between +1 and +2. Of course, when I set the parameters manually (e.g. ISO 50, Tv 2 seconds, Av 3.5) there is no need for exposure compensation.
As for the camera resolution, there is little room for myths. The higher is the resolution the camera sensor supports (without overcrowding the pixels) the better are the details of the picture. You need the details when shooting a document with very small print. Although small print comes usually in small size printed objects (like business cards) and the camera can be zoomed to fill the frame with the picture of the object (which means dpi equivalent of 600 or even 1200 dpi), there are some publications of bigger sizes with very small print.
An example of such a small print are instructions for the use of medicines provided by pharmaceutical companies which are difficult to read even with the strong glasses. I took pictures of such a leaflet at two different zoom levels to see what difference the magnification makes to the OCR. The higher is the zoom the higher is the dpi equivalent. The OCR error/warning rate changed from 2% to 1% with the two times higher zoom. So the resolution matters.