{"id":30149,"date":"2024-11-25T01:03:53","date_gmt":"2024-11-25T05:03:53","guid":{"rendered":"https:\/\/phsc.ca\/camera\/?p=30149"},"modified":"2024-11-23T23:38:35","modified_gmt":"2024-11-24T03:38:35","slug":"squaring-a-different-circle","status":"publish","type":"post","link":"https:\/\/phsc.ca\/camera\/squaring-a-different-circle\/","title":{"rendered":"squaring a different circle …"},"content":{"rendered":"
\"\"<\/a>

a lens board and a brass Cooke Primoplan 4 inch, f\/6.3 lens<\/p><\/div>\n

Toronto<\/strong>. From the beginnings of photography until well into the last century a common camera design was the field camera or its many variations. Basically the sensitive media was separated from the lens and (when needed) shutter mechanism by a sliding box affair, bellows, etc.<\/p>\n

Early on it was determined that the lens board and its lens could be swapped out to vary the focus of the camera. A rack and pinion, sliding box, friction mechanism, etc allowed the lens-to-media distance to be changed to focus the subject on the media.<\/p>\n

In yesterday’s auction was a Cooke Primoplane lens mounted on a Taylor, Taylor, Hobson (TT&H) lens mount and lens board. Someone won lot 391 and took home this gem. The brass lens is marked 4 inch (focal length), f\/6.5, Series VIIA. As a lens name Cooke<\/a> is still quite active while the name TT&H seems to have faded into history (Cooke was once a trade name for lenses designed by a different mr Taylor and manufactured by TT&H).<\/p>\n

Kingslake in his book ,”A History of the Photographic Lens<\/a>“, has an interesting section on Cooke triplets (chapter seven) and the relationship between the inventor of Cooke lenses and their \u00a0manufacturer, TT&H.<\/p>\n","protected":false},"excerpt":{"rendered":"

Toronto. From the beginnings of photography until well into the last century a common camera design was the field camera or its many variations. Basically the sensitive media was separated from the lens and (when needed) shutter mechanism by a … 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":[4673,401,3948],"class_list":["post-30149","post","type-post","status-publish","format-standard","hentry","category-history","tag-cooke","tag-lens","tag-lens-board"],"_links":{"self":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/30149","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=30149"}],"version-history":[{"count":3,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/30149\/revisions"}],"predecessor-version":[{"id":30153,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/posts\/30149\/revisions\/30153"}],"wp:attachment":[{"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/media?parent=30149"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/categories?post=30149"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/phsc.ca\/camera\/wp-json\/wp\/v2\/tags?post=30149"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}