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Long Range Hunting & Shooting
Your eye vs. optimal mm scopes?
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<blockquote data-quote="Hugnot" data-source="post: 2908582" data-attributes="member: 115658"><p>Unit is - lux.</p><p></p><p>3 or 4 for night with no moon</p><p></p><p>about 50,000 for direct sunlight</p><p></p><p>The eye pupil will dilate or contract. About 7mm max to about 3 minimum. Objective lens divided by power gives exit pupil. So 56mm/20 = 2.8 mm. </p><p></p><p>Other stuff being - from Wikipedia</p><p></p><p>"The <strong>Rayleigh criterion</strong> shows that the minimum angular spread that can be resolved by an image forming system is limited by <a href="https://en.wikipedia.org/wiki/Diffraction" target="_blank">diffraction</a> to the ratio of the <a href="https://en.wikipedia.org/wiki/Wavelength" target="_blank">wavelength</a> of the waves to the <a href="https://en.wikipedia.org/wiki/Aperture" target="_blank">aperture</a> width. For this reason, high resolution imaging systems such as astronomical <a href="https://en.wikipedia.org/wiki/Telescope" target="_blank">telescopes</a>, long distance <a href="https://en.wikipedia.org/wiki/Telephoto_lens" target="_blank">telephoto camera lenses</a> and <a href="https://en.wikipedia.org/wiki/Radio_telescope" target="_blank">radio telescopes</a> have large apertures."</p><p></p><p>Small aperture width, more diffraction & image degradation. Light from a tiny little exit pupil of 2mm or smaller will easily fit into any eye pupil.</p><p></p><p>Diffraction - bending of light waves caused by the aperture becoming a secondary source (propagating) of light waves - light spreading, less intensity. making an increased dull fuzzy image or sometimes an image consisting of concentric rings.</p><p></p><p>And</p><p></p><p>Optical science guys use the term - "numerical aperture" or NA to describe a lens. A lens with a bigger NA has a bigger angle of acceptance, like a cone with a larger diameter as related to cone height or length. This results in more light being gathered in the pointy end of the cone providing better resolution.</p><p></p><p>Glass quality & coatings matter. Some 40 mm objective lens scopes are noticeably brighter than other 50mm objective lens scopes - both set at the same power.</p><p></p><p>Scopes with fat tubes like 30mm & 34mm will have internal lenses having larger NA's.</p><p></p><p>A nice 34/56 scope would be as good as it gets.</p><p></p><p>Whatever -never ever look at the sun directly with or without an optic.</p></blockquote><p></p>
[QUOTE="Hugnot, post: 2908582, member: 115658"] Unit is - lux. 3 or 4 for night with no moon about 50,000 for direct sunlight The eye pupil will dilate or contract. About 7mm max to about 3 minimum. Objective lens divided by power gives exit pupil. So 56mm/20 = 2.8 mm. Other stuff being - from Wikipedia "The [B]Rayleigh criterion[/B] shows that the minimum angular spread that can be resolved by an image forming system is limited by [URL='https://en.wikipedia.org/wiki/Diffraction']diffraction[/URL] to the ratio of the [URL='https://en.wikipedia.org/wiki/Wavelength']wavelength[/URL] of the waves to the [URL='https://en.wikipedia.org/wiki/Aperture']aperture[/URL] width. For this reason, high resolution imaging systems such as astronomical [URL='https://en.wikipedia.org/wiki/Telescope']telescopes[/URL], long distance [URL='https://en.wikipedia.org/wiki/Telephoto_lens']telephoto camera lenses[/URL] and [URL='https://en.wikipedia.org/wiki/Radio_telescope']radio telescopes[/URL] have large apertures." Small aperture width, more diffraction & image degradation. Light from a tiny little exit pupil of 2mm or smaller will easily fit into any eye pupil. Diffraction - bending of light waves caused by the aperture becoming a secondary source (propagating) of light waves - light spreading, less intensity. making an increased dull fuzzy image or sometimes an image consisting of concentric rings. And Optical science guys use the term - "numerical aperture" or NA to describe a lens. A lens with a bigger NA has a bigger angle of acceptance, like a cone with a larger diameter as related to cone height or length. This results in more light being gathered in the pointy end of the cone providing better resolution. Glass quality & coatings matter. Some 40 mm objective lens scopes are noticeably brighter than other 50mm objective lens scopes - both set at the same power. Scopes with fat tubes like 30mm & 34mm will have internal lenses having larger NA's. A nice 34/56 scope would be as good as it gets. Whatever -never ever look at the sun directly with or without an optic. [/QUOTE]
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Your eye vs. optimal mm scopes?
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