10" Commercial Ektar question

<p>I was looking through a vintage Kodak booklet on lenses/shutters and noticed the spec.s of the 10" Commercial Ektar listed as being able to cover the whole plate format (6-1/2" x 8-1/2") and the recommended lens for use in that format, etc. That made me to wonder why would Kodak make a lens for an obsolete format that was obsolete even in the day the Commercial Ektar was built? I realize the lens can be used on a 5x7 and many people no doubt used it on their 5x7 but, the question remains, was anyone still using whole plate cameras even in the 1950s and what was Kodak thinking producing a whole plate format lens?</p>

<p>The brochure was stating the maximum coverage the lens was capable of achieving, in a quick-reference format, instead of stating the maximum circle-of-coverage, using a known/common format size of the day. Simple, quick, and easy.</p>

<p>Most lens types, were made in a range of focal lengths. In the case of the f6.3 Commercial Ektars post-1940's versions the available focal lengths were 8.5 in, 10 in 12 in, 14 in. All of these lenses were made to the same pattern with 4 elements in three groups, after the Tessar design. So all the lenses in a series would have had similar characteristics, with image circle increasing along with focal length.</p>

<p>Anyone using one would then know immediately what coverage was available. And in using one on, say, 4x5 or 5x7 then the amount of available movements would also be known. </p>