I'm curious as to why you have chosen the 50mm as a portrait lens? I'm not sure of the conversion from traditional slr to digital, but won't the 50mm in effect become a wide-angle lens? Probably better suited for landscape work? Surely the best choice for portraits would be something that would be equivilant to a 105mm lens. Which is traditionally the best focal length for portraits. Again as I said I'm not sure of what focal length changes become when converted to digital. Donald is our resident Canon user, recently converted to digital. He's also very knowledgable in the technical stuff so maybe he can help you with this.

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