What is the difference between the APO-Ronar and the APO-Ronar-CL lens? Is the latter suitable for landscape photography? I assume the APO-Ronar is, as it is current sold by various camera stores.
I am looking for a lightweight 360mm lens and the G-Claron is a little bigger than I would like, so I have been researching the Rodenstock line. I understand the Fujinon-A is a candidate, but is extremely hard to find (per the info at Kerry Thalmann's website).
The CL Ronar uses a special compound to hold the elements in alignment through extremes of temperature. When manufacturers changed from brass to aluminum to make lens mounts/barrels they found/already knew that aluminum expanded/contracted more than brass did and most just allowed a little more slop to cover. Rodenstock made this compound to ensure that the elements stayed in the factory set positions. A chap in the process lens recalibration/repair field told me that little snippet and he often bemoans aluminum barreled lenses as being inferior to brass ones.He's one of the top dogs in that biz so tend to take his information without any salt.
CP Goerz
Linearized aperture scale vs non linearized aperture scale. Both are corrected for 1:1 of 2 dimensional art. Neither is corrected for landscapes.
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.
Actually the factory states that the Apo Ronars are optimized for 1:1 but since they are symmetrical designs that they work out to infinity and would out perform most Tele designs. But the will not equal the N or S or W Sironars at those ratios.
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