Difficulty and challenge with vintage or non-modern view camera lenses are their shutters. Majority of these lenses in shutter will have shutters that need service or have died. Older shutters like Ilex, Compur, and such have round iris apertures. This aids significantly to out of focus rendition beyond the innate out of focus rendition of the lens formula.
Modern Copal, Compur, and similar shutters have non-round iris aperture putting them at a disadvantage for aiding with the designed in lens out of focus rendition.
Barrel lenses from that era like kodak Ektar and more will have a very nice round iris aperture. Some of the very best lenses of this variety are in barrel and were never made in shutter. This is why a camera system with shutter like Sinar is and has become highly desirable today. It is directly due to the awareness of the innate optical goodness only barrel lenses offer that lenses in shutter cannot.
Tessar lens formula goes back to about 1902 by Paul Rudolf at Zeiss. Since time the Tessar has become one of the great and very common photographic lens design to this day. Typical Tessar offers GOOD out of focus rendition at full lens aperture (typically f4.5 and smaller) with near ideal performance two f-stops down from full aperture. There is ZERO modern lens design have over this appearing simply lens design from over a century ago. Newer is not always better, there are SO many factors that influence out of focus rendition.
Kodak f4.5 Ektar, Kodak Commercial Ektar f6.3 are Tessar designs using Lanthium glass which aid much in color correction and color rendition.
Take the time to read this previous discussion:
https://www.largeformatphotography.i...r-lenses/page3
Multi-coated lenses are not worth obsessing over with many view camera lenses. In the specific case of a Tessar design, it has GOOD performance due to it's simplicity and limited number of glass to air surfaces. Single coated Tessar (Kodak EKtar, Xenar and ..) are excellent performers for this and other reasons. Softer contrast rendition of Tessar designs like Kodak Ektar, Xenar and ... can be a image advantage over modern multi coated Plasmat lens designs that tend to offer higher contrast rendition but not higher resolution than a Tessar lens design. Typical Tessar has about 60 degrees angle of good lens image circle performance. Know the modern multi coated Plasmat has been specifically designed to produce high contrast images optimized at f22 intended to render most all areas of the image area in apparent focus. Tessars can and are often used at full aperture for their out of focus rendition qualities.
From a previous LFF discussion:
https://www.largeformatphotography.i...t-work-on-8x10
Bernice
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