Book publication translates to printing.
More megapixels are needed for printing.
And considering that most photos need some degree of cropping.....that calls for more megapixels.
Stay with the largest size and least compression.
Use Large and High Quality.
It will take up more space on the memory card.
Buy more memory cards instead of compromising your photos.
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The A620 has five resolution settings (large, middle 1, middle 2, middle 3, and small) and three compression settings for each one (high quality, normal, and lowest). My photographs will be used almost exclusively in power point presentations and book publication. I am new to this camera but I am headed for India in two weeks. If someone familiar with this camera could tell me what setting would suffice for book publication I would be grateful; I will use that as my minimum setting in regard to quality. Thanks for your help.

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