{"id":23777,"date":"2022-08-01T01:03:32","date_gmt":"2022-08-01T05:03:32","guid":{"rendered":"https:\/\/phsc.ca\/camera\/?p=23777"},"modified":"2022-08-01T00:00:07","modified_gmt":"2022-08-01T04:00:07","slug":"lens-board-connects-to-the-lens-mount","status":"publish","type":"post","link":"https:\/\/phsc.ca\/camera\/lens-board-connects-to-the-lens-mount\/","title":{"rendered":"lens board connects to the lens mount"},"content":{"rendered":"
\"\"<\/a>

a wooden lens board and lens with a lens mount squeezed in-between the two<\/p><\/div>\n

Toronto<\/strong>. For most of the 1800s and early 1900s, cameras had a focussing means situated between the lens board and the media making the media-to-lens distance relatively unimportant. However; when camera bodies became rigid and the focussing means moved to the front of the lens board, the distance between the media and the lens mount<\/a>\u00a0(flange) became critical if a lens was to focus at infinity.<\/p>\n

If that distance was wrong for a given lens, it could not focus at infinity on that particular camera. In the early days of minicams such as the Leica, lenses were fixed and a lens could be factory \u00a0calibrated to suit a given body. Once interchangeable lenses were offered, the media to lens mount distance became critical. Briefly Leitz made lenses to suit a given camera and only offered the lens choices during manufacture.<\/p>\n

A rapid change to a standard<\/a> media-lens mount distance (29.9mm for Leica) resolved this problem and afterwards any lens would fit any Leica camera that had the standard distance. Thoughtfully, when the M-mount cameras went on sale, they had a media to lens mount distance of 28.9mm allowing a 1mm ring to be used between screw mount lenses and bayonet mount camera bodies (M-series).<\/p>\n

Note. the title of this post is a riff on the kids’ song, “The Skelton Dance<\/a>” which itself was a simplified version of “Dem Bones<\/a>” which I often heard as a child.<\/p>\n","protected":false},"excerpt":{"rendered":"

Toronto. For most of the 1800s and early 1900s, cameras had a focussing means situated between the lens board and the media making the media-to-lens distance relatively unimportant. However; when camera bodies became rigid and the focussing means moved to … Continue reading →<\/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":[14,563,3948,2193,279],"class_list":["post-23777","post","type-post","status-publish","format-standard","hentry","category-history","tag-film","tag-glass-plate","tag-lens-board","tag-lens-mount","tag-lenses"],"_links":{"self":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/23777","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=23777"}],"version-history":[{"count":2,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/23777\/revisions"}],"predecessor-version":[{"id":23781,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/23777\/revisions\/23781"}],"wp:attachment":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/media?parent=23777"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/categories?post=23777"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/tags?post=23777"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}