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Message: <blockquote data-quote="Binastro" data-source="post: 3136517" data-attributes="member: 111403">. Hi pesto,I suspect that a platonic relationship is not what they mean, maybe they mean aspheric.If you find the top left star in the constellation of Orion and the leftmost star in the belt of Orion, which has three bright stars.The distance between these two stars is almost exactly 10°, perhaps a shade more.If however, the 7×25 monocular does not encompass both these stars then try the bottom two bright stars in the constellation of Orion, from memory 8.35° apart but I will check.The distance between stars can be calculated to high accuracy and it is very clear what the field of view is. But this may vary from person to person, I suppose depending if they are shortsighted or longsighted etc and also where they place their  eye.In my experience, only the top binoculars accurately describe their field of view, and other specifications. The majority of binoculars are not as described, even the weight can be wildly different, which seems very odd to me, as it is not difficult to weigh a binocular.</blockquote>