Hello, Bob,Originally Posted by Bob Salomon
years ago, a wise man from Rodenstock Germany, I forgot his name, sorry, told us, that if my 480er Apo Ronar sits in a shutter, it is corrected for ininity.
Rodenstock created this difference to non shutter Apo Ronars by using / not using a kind of spacer, and one can do this job alone, at home.
Ritchie
Ritchie, the spec sheets showed them corrected for 1:1 in or out of shutter.
I know, 1:1 was the original concept, but Rodenstock gave a second possibilty, too.
In germany, the thing with the spacer is well known to some photographers.
If you open your Ronar (480, the others I don't know), you can see by looking at the spacer, or the missing spacer, which correction is given.
As said before,this was an official tale from Rodenstock to customer.
Do you know the name of the last old man with experience in older lenses, who worked at Rodenstock? I can't remember, sorry, it may be 10 or 15 years ago..
Wait a minute - there is a german astronomic forum, where another ex-specialist from Rodenstock gave great informations about the Ronars, too, and in my memories, he has said the same.
If you want to know more, we can do a timerobbing research, because I don't know the name of the forum anymore nor the name of the thread, but it had something to do with - Ronars.
During searching informations around my not so often 520er Apo Ronar, I had found this thread...
Ritchie
I was the Rodenstock Product and Sales Manager in the US and all the information that the factory gave us was for 1:1. In and out of shutter. Think about it a minute. When the factory put the lens into a shutter at the factory they had no way of knowing if it would be used by the eventual consumer for 1:1 or for infinity.
Great luck, Bob, after some minutes i found the information !
http://forum.astronomie.de/phpapps/u...objektive_fur_
No 747, from Mr. Walter E. Schön, who has had to do at thistime, anno 2004, with the technical documentation around Rodenstock lense.
In translation, he described , why an Apo Ronar, constructed for 1:1, not depend so much on given ratio - because of the thin lenses, the symmetrical concept and big "Krümmungs radius". This must mean the radius of the "convex"..
He also explained, that the ApoRonars from 150 to 480mm came in barrels, but also in shutters.
In this case, the space between lense were changed with a tiny factor.
And i know, that this factor is given by thin shims.
This, I haven't forget :-)
Ritchie
Walter is a good friend and he is Dr, not Mr. Among other things he designed the Rodenstock Scheimpflug/DOF calculator and wrote many white papers for Rodenstock. But the lens is still not designed for general infinity shooting and will be inferior to an Apo Sironar - or S. In addition the Apo Ronar is corrected for f22 only where as the Sironar designs, besides having far greater coverage, also have a greater range for optimal aperture.
""When the factory put the lens into a shutter at the factory they had no way of knowing if it would be used by the eventual consumer for 1:1 or for infinity. ""
I have heard two same opinions from two different Rodenstock workers, and yes, I know from the forum about your great Rodenstock job.
I know one guy, who has bought the last Apo Ronar 480mm from Rodenstock after stopping the production, and during buying the lens, he has had some interesting small talks with the Rodenstock man. So he got the information about the ratio and the spacers this way.
Maybe Rodenstock in germany asked the customer in general for the task of the lens and the need of the shims, or maybe Rodenstock decided by themselves to build in a spacer. I don't know; reading Dr. Schön, it seems, that Rodenstock made this atomatically.
But they really did, and there exist two versions, one constructed and corrected for 1:1, and one secondway-corrected for infinity.
Ritchie
Last edited by plaubel; 10-Dec-2015 at 08:20.
There is a Sinar version of the CL that can be taken apart where one will find two shims. It seems to make sense that removing one of these would adjust the optimization.
We were the Rodenstock distributor for the photographic industry in the USA and, as such, only sold Apo Ronar lenses factory mounted in shutters. For the graphic arts industry the Apo Ronars in barrel mount were imported and distributed by, first, Rodenstock USA and then later by Linos after Linos bought Rodenstock Precision Optical. In all literature and discussions that we had with the factory, from our becoming the Rodenstock distributor in 1986 till the end of the production the lenses we were told that they were all designed for 1:1 but that they were useable at infinity but would not perform as well as the Sironar-N, Apo Sironar-S, or Apo Sironar series lenses. We also know, from both spec sheets and working with major studios for advertising photos of fine products that they also did not equal the Makro and Apo Macro Sironar lenses for product work. However they were far better then either for copy work.
How many shims can dance on the head of a pin?
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