Lenses covering 20 x 24

[Stewart Ethier]

Since both Wisner and Lotus View make 20 x 24 cameras, there must be lenses that cover this format. This means an image circle of diameter at least 800mm, pref erably 900mm to allow for movements. Does anyone know what's available? In par ticular, what is the choice of focal lengths?

[Sean Donnelly]

The Lens and Repro Equipment Corp. has advertised a 150 mm Goerz Hypergon that c overs 20 x 24". I believe ther are also many long focal length process lenses t hat would cover this size.

[Stewart Ethier]

I can now answer my own question to some extent, in case anyone's interested. I just found in my basement a 1969 Burke & James catalog, with something like 40 pages devoted to lenses. First, there are 7 Goerz Red Dot Artar lenses that cov er 20 x 24, with focal lengths of 19, 24, 30, 35, 42, 47.5, and 70 inches. The first two are available in Acme M-X synchro shutters, while the last 5 are avail able only in barrel. The coverages of the 7 lenses are respectively 20 x 24, 24 x 32, 30 x 40, 36 x 45, 48 x 56, 48 x 64, and 72 x 90 inches. Actually, the ca talog says "covers at same size", but I'm not sure exactly what this means. Doe s it mean at 1:1? Are these lenses intended for close-up work?

The catalog contains 7 pages of anastigmat lenses, but only two cover 20 x 24: both Goerz Dagor Series III f/7.7 in barrel. The 24 inch version covers 18 x 36 , while the 30 inch version covers 30 x 40.

Finally, there are two pages of process and copy lenses, and I counted 24 of the m that cover 20 x 24 or more. Manufacturers include Goerz, Rodenstock, Carl Zei ss, Boyer, Metra, Taylor Cooke, Ross, and Wray.

Presumably, most of these lenses are available on the used market. The prices i n the catalog seem very low---I guess there's been some inflation in the past 30 years!

[Boyd Hecker]

Wisner has a 20 X 24 Lens Guide (posted 4/30/99) listing "classic" lenses with a promise to add 'certain recent production lenses to this table in the near future.' http://wisner.com/20x24lens.htm

[John Hicks]

Artars are process lenses, intended for 1:1 or so, which is most likely what tha t coverage spec refers to.

[Tracy Storer]

Stewart, "covers at same size" DOES mean 1:1, You would need an Artar of 30" or more to cover 20x24 at infinity. Dagors from 16.5"(no movement) and up will do nicely. Zeiss wide angle Protars in longer focal lengths(rare) are great. Fujinon 600 C is my main lens for infinity to 1.5:1. Tracy Storer www.mammothcamera

[Murph]

Good information.

[RichardRitter]

Wisner has a 20 X 24 Lens Guide (posted 4/30/99) listing "classic" lenses with a promise to add 'certain recent production lenses to this table in the near future.' http://wisner.com/20x24lens.htm

The Wisner site is no longer on line.

[Tracy Storer]

Screenshot courtesy the wayback machine.....

[Mark Sawyer]

Just out of curiousity, has anyone ever tried popping a good negative diopter on a lens, thereby increasing its focal length and coverage?