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Message: <blockquote data-quote="Chosun Juan" data-source="post: 3533403" data-attributes="member: 92780">I don't agree with that - I think the most beneficial figure for spectacle wearers is one indisputable mandatory ISO physical measurement. Of course then you also need dimensions and photos of the eye cups to be useful as an indicator when making a 'remote' purchase, such as a physical sight unseen Internet order for those without better options. The individual quickly learns what sort of impact various eye cup designs have on the users current or potential spectacles and script.Just going from memory, so could be a bit dodgy, but I seem to recall there being an International Standard for measuring Eye Relief which is defined as the coaxial distance from the exterior of the ocular lens to the exit pupil. This is how it should be. It is the only valid means for comparison.  This of course assumes that companies are getting even the basics like having the correct figures on websites/specs etc!  :cat:As has been said, there are so many other variables with an individual (prescription, glasses design, facial characteristics, ipd, symmetries, offsets etc), the bin's optical design parameters, ocular dimensions, eye cup design, and the myriad permutations of how this all marries up together, that I believe any attempts to provide an effective eye relief figure would be too inconsistent and erroneous.Chosun  :gh:</blockquote>