270mm f/10 APO-Gerogon S vs. 300mm f/9 APO-Gerogon

[Craig Wactor]

I am trying to locate info on these two lenses for use with 11x14. Specifically, the coverage circle of the 270, and how much, if any, movement would be available with that format. My search here and on google Does anyone own either of these lenses?

[Oren Grad]

The Apo-Gerogon is specified as covering 70 degrees at f/22. For a 300mm focal length that should put it just shy of 11x14 at infinity. The Apo-Gerogon-S is supposed to cover 75 degrees, but at the focal length of 270mm, you'd get an image circle a bit less than a 300 at 72 degrees.

I'll anticipate Bob here, and toss in the disclaimers - the Apo-Gerogon is designed as a wide-angle process lens for compact vertical copying cameras, and is intended to be used at f/22 for reproduction ratios from 1:5 to 1:1. The Apo-Gerogon S is also designed to be used at f/22, for reproduction scales from 1:3 to 3:1.

[Craig Wactor]

thanks, Oren

[Joerg Krusche]

Craig,

threads of front and rear cells of the 9/300 Apo Gerogon CL screw direct into a Copal 3 shutter, the only thing you have to do is to get two rings to adjust for spacing, which is not critical since a symmetrical lens design. Optical performance should satisfy all needs.

Best regards

joerg

[Dan Fromm]

Joerg, are you thinking of an Apo-Gerogon or an Apo-Ronar? I ask because I've seen Apo-Ronar CL lenses but no -CL Apo-Gerogons.

Cheers,

[Joerg Krusche]

Dan,

I am talking about the Apo Gerogons,

just like the Apo Ronar's they (240/300/360) were as well available as CL versions, same housing as the Apo Ronar's. BTW the Apo Gerogons are very good at infinity, some might call them sleepers with their wide picture angle of 70+ degrees.

Best regards

Joerg

[Oren Grad]

Joerg, do the Apo-Gerogons continue to gain usable coverage as you stop down beyond f/22, as the G-Clarons do?

[Joerg Krusche]

Oren,

sorry, I only looked at them with 4x5/13x18(5x7), so no experience.

Best regards

Joerg

[Craig Wactor]

What does the CL mean? Is it marked on the lens (APO-Gerogon-CL)?

[Oren Grad]

Craig -

Check out this thread about the Apo-Ronar CLs - not sure whether the interpretation would be the same for an Apo-Gerogon CL, but perhaps Bob can tell us:

largeformatphotography.info/lfforum/topic/496873.html (http://largeformatphotography.info/lfforum/topic/496873.html)

[Struan Gray]

joerg, do you know of any good sources for used Apo-Gerogon CL's?

I have just bought a 270 mm f11 Apo-Gerogon-S, after a long patient wait for a bargain. In all that time I haven't seen a single CL offered for sale. If you know of a secret stash, or a place where owners congregate to sell, I'd love to know.

[Joerg Krusche]

Struan,

only the 240/300/360 Apo Gerogons come in that body, the 270 S has the same "double-tapered" body as the other Apo Gerogons. The nice thing about the 300mm is the fact that no great machining is needed since the threads are there, you only need to make two distance-rings (spacers ?) to adjust for the original spacing or even increase it a bit. I believe the 270 S is a good lens, in case you were still interested in the 9/300 Apo Gerogon (CL body) just because it is so simple to make it fit, let me know, I could perhaps make available some NIB (in the true meaning of this) lenses. I recently "tested" one of the 300's on a SL66 and APX 25/Rodinal 1+75, ...center sharpness on 120 film is impressive. There is no reason why this lens, with some stopping down should not be satisfacory for LF, at least the MF curves are at least as good as for the Apo Ronar, but with a larger usable image circle.

You may contact me direct.

Best regards

Joerg

[Bob Salomon]

There is no reference to an Apo Gerogon CL in the factory literature back to the 1970's, However CL to Rodenstock means a linearized aperature scale and all Apo Gerogon lenses that we have illustrations of have a linearized aperature scale - we have very few pictures though.

Rodenstock lists the following Apo Gerogon series; Apo-Gerogon, Apo-Geragon S and the Apo-Graphigon.

All are wide field process lenses with coverages between 70 and 78°. The S was made in 270mm only and covered 75°. The Apo Graphigon was made in 240mm and covered 78°. The Apo-Gerogon was made in 150mm to 360mm and covered 70 to 78° depending on the lens.

According to Rodenstock's product manager when we asked about making these lenses available in shutter in the mid 80's the cells will NOT fit directly into a shutter without an adapter. The narrower angle Apo Ronar lenses (modern versions) would up to 480mm.
The Apo-Ronar series was available in a CL version with lenses from 240mm to 1800mm. As noted earlier CL simply means a linearized aperature scale. It does not indicate different optical properties from a non-CL Rodenstock lens.

[Bob Salomon]

"Specifically, the coverage circle of the 270,"
Craig,

Per Rodenstock the 270mm f11 is designed to cover film formats up to 20 x 24" at 1:1 and is designed for ratios of 1:3 to 3:1.
The 300mm f9 is designed to cover film up to 22 x 26" at 1:5 to 5:1.

All are based at f22.

Of course at infinity the circles are smaller.

[Craig Wactor]

Thanks for all of the great answers. I think I am going to buy the 270 f/11, and see how I like using it.

[Oren Grad]

Craig, when you've had a chance to use it, please do report back on your experience!

[Craig Wactor]

Sure will!

[jayavant]

I just bought a Rodenstock Apo-Geragon S 270mm F11 on Ebay in great condition and am itching to use it with 8x10. Can anyone point me to information about the thread sizes and the adaptor rings I will need to fit this to a shutter?

[Dan Fromm]

The Rodenstock Process Lens Manual's drawings give mounting thread dimensions, not cell spacing or the cell threads' dimensions.

Your best bet is to send the lens to a photographers' machinist, e.g., www.skgrimes.com, and ask for an estimate.

Before you do that, unscrew the cells and measure their threads' diameters. Compare with shutters' front and rear threads, which can be found starting from here: http://204.12.25.18:7883/products/new-copal-shutters If there's a target shutter that will do -- each cell has to be smaller than the end of the shutter it will go into -- then adaptation is possible.

Unless you have the right shutter on hand, adaptation may not be cost-effective, i.e., tossing y'r Apo-Gerogon S and buying a used 270 plasmat in shutter and having its shutter made right may cost less than a used shutter made right and having threaded bushings made. I hope you're prepared for this.

The 270/9 G-Claron's cells are direct fits in a #1 shutter. And now you know why Apo-Gerogons sell for less than comparable G-Clarons.

[Emmanuel BIGLER]

This thread started in 2005 !!

The documentation pages mentioned by Dan and relevant to apo gerogon and graphigon barrel lenses are here to download. (http://www.cijoint.fr/cjlink.php?file=cj201011/cijZJOiVv4.pdf)

[Bob Salomon]

I just bought a Rodenstock Apo-Geragon S 270mm F11 on Ebay in great condition and am itching to use it with 8x10. Can anyone point me to information about the thread sizes and the adaptor rings I will need to fit this to a shutter?

These lenses will not screw directly into a shutter. Someone will have to make you adapters.