{"id":22712,"date":"2022-02-15T01:23:45","date_gmt":"2022-02-15T05:23:45","guid":{"rendered":"https:\/\/phsc.ca\/camera\/?p=22712"},"modified":"2022-02-15T01:43:18","modified_gmt":"2022-02-15T05:43:18","slug":"about-that-land-in-florida","status":"publish","type":"post","link":"https:\/\/phsc.ca\/camera\/about-that-land-in-florida\/","title":{"rendered":"about that land in Florida"},"content":{"rendered":"<div id=\"attachment_22713\" style=\"width: 163px\" class=\"wp-caption alignleft\"><a href=\"https:\/\/phsc.ca\/camera\/wp-content\/uploads\/2022\/02\/Coated-lenses-Popular-Mechanics-May-1940-1.jpg\"><img loading=\"lazy\" decoding=\"async\" aria-describedby=\"caption-attachment-22713\" class=\"size-full wp-image-22713\" src=\"https:\/\/phsc.ca\/camera\/wp-content\/uploads\/2022\/02\/Coated-lenses-Popular-Mechanics-May-1940-1-sm.jpg\" alt=\"\" width=\"153\" height=\"225\" \/><\/a><p id=\"caption-attachment-22713\" class=\"wp-caption-text\">demonstrating lens coating in America just months before they entered WW2<\/p><\/div>\n<p><strong>Toronto<\/strong>. An article in the May 1940 issue of Popular Mechanics suggests a coating can double the lens speed (if only this were so &#8230;). We used to suggest to gullible people that if they believed something improbable, we have some (swamp) land in Florida they might like.<\/p>\n<p>In reality, <a href=\"https:\/\/www.shutterbug.com\/content\/why-lens-coatings-are-so-important-these-lovely-layers-are-more-just-pretty-face\">coating<\/a> lens elements <em>does<\/em> increase the light transmission through a lens and may mean a smaller aperture can give the same amount of light to the sensitive media, <em>but<\/em> most obvious to a photographer is the increase in contrast and the saturation of colours (plus the capability to increase the number of lens elements without rapidly increasing internal reflections [zoom lenses anyone?]). Wikipedia gives a more <a href=\"https:\/\/en.wikipedia.org\/wiki\/Anti-reflective_coating\">technical explanation<\/a> of lens coatings as anti-reflective coatings.<\/p>\n<p>The lens &#8216;speed&#8217; or <a href=\"https:\/\/en.wikipedia.org\/wiki\/Aperture#Maximum_and_minimum_apertures\">aperture<\/a> is a basic mathematical function: \u00a0focal length divided by the effective lens diameter or simply the f\/stop. Compare, for example the coated post war and uncoated pre war Elmar 90mm lenses. Both are f\/4 aperture but the coated lens gives far better contrast and colour saturation than its older sibling.<\/p>\n<p>And another &#8216;tip of the hat&#8217; goes to my good friend, George Dunbar for sharing this article with us.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Toronto. An article in the May 1940 issue of Popular Mechanics suggests a coating can double the lens speed (if only this were so &#8230;). We used to suggest to gullible people that if they believed something improbable, we have &hellip; <a href=\"https:\/\/phsc.ca\/camera\/about-that-land-in-florida\/\">Continue reading <span class=\"meta-nav\">&rarr;<\/span><\/a><\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1944],"tags":[885,2017,4040,578],"class_list":["post-22712","post","type-post","status-publish","format-standard","hentry","category-history","tag-america","tag-article","tag-lens-coating","tag-ww2"],"_links":{"self":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/22712","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/comments?post=22712"}],"version-history":[{"count":3,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/22712\/revisions"}],"predecessor-version":[{"id":22716,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/22712\/revisions\/22716"}],"wp:attachment":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/media?parent=22712"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/categories?post=22712"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/tags?post=22712"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}