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Message: <blockquote data-quote="typo" data-source="post: 3170781" data-attributes="member: 83808">I think we are already stumbling into some of the pitfalls of this topic. Just because two instruments appear to show the same level of detail to the eye it doesn't mean they have the same resolution or even effective resolution.A binocular as an instrument has a resolution primarily dictated by the full aperture objective. It also has an effective resolution which is dictated by the diameter of the objective corresponding to the diameter of the pupil of the eye when observing. So if your pupil is 2.5mm diameter than the effective aperture with an 8x42 for example is 2.5x8= 20mm. So the effective resolution for 20mm applies. Those with excellent eyesight might see the 'sharpness' differences due to effective resolution in optimum light conditions on top of other properties. The rest of the time the detail will be limited by the acuity of the user's eyesight as it normally would be for those with more typical eyesight. Then any perceived sharpness differences will be due differences like contrast and colour contrast not effective resolution.Cheers,David</blockquote>