I have a lot of digital photos and although the photos have details like F stops and others settings linked to its properties, I need to also add other information about the photo subject to it. Does anyone know if there is a pieace software that have this feature?

Photoshop has a really good "caption" function that will allow you to add details. If you want to search for keywords, though, go with Extensis Portfolio. It is excellent. You can find both on eBay.

WR1000
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Exchrome Visual Services