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Message: <blockquote data-quote="Kevin Purcell" data-source="post: 1525004" data-attributes="member: 68323">It's all in the prism Frank. It down to the specification of the prism (if they're all like this) or the particular prism in my case.I also speculate that in some cases if it's responsible for the "roof look" of some roof prism bins. That off but not quite sharp look that porros (even cheaper ones) don't suffer from but seems "common" amongst low and mid-priced roofs. I note that the Zeiss I have that don't have diffraction spikes also don't have the "roof look".The bare minimaglite test is an easy in-store test for those that wish to screen for this.</blockquote>