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Message: <blockquote data-quote="Jim M." data-source="post: 1317724" data-attributes="member: 60675">This is certainly getting confusing!  So I guess you are claiming that XD is simply a marketing-driven name change from ED?  But your first two paragraphs seem to contradict each other.  You say in your first paragraph that the Prominar label applies to any scope that uses fluorite crystal lenses, (and that label is applied on the Kowa website to the 663, 773,  and 883).  But then you say in your second paragraph that only the 883 has a fluorite crystal lens.  I do not see how both these claims can be true.In any event, looking at the Eagle Optics website, it lists certain coatings as being on the 773 lenses which are not mentioned in the description of the 663.  ("C3 Coating is a highly reflective multi-coating of dielectrics for a much higher reflectivity than with coatings of silver or optically-enhanced aluminum, offering a reflectance of 99% or higher across the entire visible spectrum"). So I still believe that the 773 has technology that the 663 lacks.Best,Jim</blockquote>