20x24 lenses

[Mark Sawyer]

If you're doing still lifes, the Tessar may well cover at close distance.

[Dan Fromm]

Algo, as a newcomer here you may not be aware of this site's resources. The first post in this https://www.largeformatphotography.i...mainly)-lenses discussion has a link to a set of links to sites etc. of interest to LF photographers. One of the links answers the question -- how does a lens coverage grow with magnification? -- you sort of asked.

Since, however, you have the lens and know the standards to which you work, you ought to ask the lens whether it can do what you need well enough to please you.

Good luck, have fun.

[Algo después]

"with a negativ lens -1 dioptrie behind the camera lens you can expand the focus to 1200mm= f:18"

Hey Mark.

Thanks for the confirmation. What do you think about this statment. It is possible ¿

[Algo después]

Algo, as a newcomer here you may not be aware of this site's resources. The first post in this https://www.largeformatphotography.i...mainly)-lenses discussion has a link to a set of links to sites etc. of interest to LF photographers. One of the links answers the question -- how does a lens coverage grow with magnification? -- you sort of asked.

Since, however, you have the lens and know the standards to which you work, you ought to ask the lens whether it can do what you need well enough to please you.

Good luck, have fun.

Thanks again Dan. I will check carefully, probably I did but I didn't get it.

Cheers

[Rod Klukas]

The 1210mm F12.5 Apo-Nikkor will cover at infinity. 878mm image circle focused at infinity. You need about 813mm to cover 20x24.
I have data on these if anyone wants it. email me or PM me.

Rod

[Rod Klukas]

Bob Soloman reported the following also some years ago:

1200mm f16 Apo Ronar CL (CL means that it has a linear aperature scale).
Effective focal length = 1200.1mm; Max. Recommended film size at 1:1 = 40 x 50", Recommended scale = 1/10x - 10x (1x); Minimum aperture = f128, Filter thread = 135mm x1; Overall length = 243mm; Flange focal length at infinity = 1171.5mm; Maximum lens diameter = 150mm, Screw thread = 145mm x1; Contact area to rear edge = 93mm.

Designed for jobs like map making. Rodenstock made 6 element 600, 800, 1000 and 1200mm Apo Ronar CL lenses. Coverage is 40 to 46° on Apo Ronar CL lenses longer then 480mm.

For the 1200mm f14 the specs are as follows:
1200mm f14 Apo Ronar CL (CL means that it has a linear aperature scale).
Effective focal length = 1199.8mm; Max. Recommended film size at 1:1 = 40 x 50", Recommended scale = 1/10x - 10x (1x); Minimum aperture = f128, Filter thread = 100mm x1; Overall length = 129.5mm; Flange focal length at infinity = 1185.3mm; Maximum lens diameter = 135mm, Screw thread = 120mm x1; Contact area to rear edge = 39.9mm.

The catalog shows them as both being 6 element.

[Rod Klukas]

Also Doug Bush produced lenses that would cover, though I believe they were made by Milles Grillot for him. See this: https://www.cameraquest.com/degoldenbusch.htm


He made cameras from 8x10 to 20x24.

Hope this is useful.

Rod