Rodenstock sironar-n 135mm APO vs. non-APO?

[altec2]

If you look at the Christopher Perez/Kerry Thalmann lens tests, they show that the 1980's non-APO labeled version of the Rodenstock Sironar-N 135mm f5.6 arguably outperformed the later 1990's APO labeled version (see results copied below).

I note they often tested the same model and saw significant sample variation--do you think that is the case here or is the later APO version really though of generally as "less good"?

Also, confusingly he makes this statement about the APO Sironar-N 135mm even though the two lenses have different weights (185g vs. 170g):

"Also, for years, it was sold as the "plain" Sironar-N (no APO moniker). There was absolutely no design changes between the plain Sironar-N line and the current APO labeled line. This change was purely marketing hype."

Why the different weights if they are exactly the same?

Rodenstock Sironar N f/5.6 135mm
f/11 48 48 24
f/16 54 54 54
f/22 60 54 54
185g Copal 0 109xxxx2 1980's

Rodenstock APO Sironar N f/5.6 135mm
f/11 38 42 30
f/16 54 60 54
f/22 48 48 48
170g Copal 0 11369xxx 1990's

http://www.hevanet.com/cperez/testing.html

[Gem Singer]

The 15gm weight difference could be the result of a change in the shutter design (from a thin shutter speed ring to a thicker ring), a slight change in the design of the lens barrel, or an error in the scale. Totally insignificant.

[Ken Lee]

Eventually, Rodenstock stopped making the N line of lenses. The APOs have greater coverage and better performance (how much remains to be seen), but I can't recall ever reading that the N lenses were inferior lenses. The sharpest lens I have tested at infinity distance is a 210 Macro Sironar N.

I wouldn't hesitate to get N lenses: they are very affordable and widely available. You might see a difference at the edges if you plan to enlarge greatly, but if you really need coverage (like for architecture or table-top) it's best to get a wide-coverage design or a macro.

Modern LF lenses from Nikon/Fuji/Schneider/Rodenstock are so good that it's generally a better idea to select based on size, weight, filter size, availability and price.

Speaking of Perez and Thalmann, have a look on Perez's site where he compares some old versus new designs in similar focal lengths. The differences are negligible even under a microscope. Modern lenses are coated, and modern coating is better than old coating, but again that's something which affects a small % of shots (unless you're shooting into the lights all the time for some reason) - and it's always a good idea to use a lens hood of some kind or other.

[E. von Hoegh]

If you look at the Christopher Perez/Kerry Thalmann lens tests, they show that the 1980's non-APO labeled version of the Rodenstock Sironar-N 135mm f5.6 arguably outperformed the later 1990's APO labeled version (see results copied below).

I note they often tested the same model and saw significant sample variation--do you think that is the case here or is the later APO version really though of generally as "less good"?

Also, confusingly he makes this statement about the APO Sironar-N 135mm even though the two lenses have different weights (185g vs. 170g):

"Also, for years, it was sold as the "plain" Sironar-N (no APO moniker). There was absolutely no design changes between the plain Sironar-N line and the current APO labeled line. This change was purely marketing hype."

Why the different weights if they are exactly the same?

Rodenstock Sironar N f/5.6 135mm
f/11 48 48 24
f/16 54 54 54
f/22 60 54 54
185g Copal 0 109xxxx2 1980's

Rodenstock APO Sironar N f/5.6 135mm
f/11 38 42 30
f/16 54 60 54
f/22 48 48 48
170g Copal 0 11369xxx 1990's

http://www.hevanet.com/cperez/testing.html

I don't know about the weight, it could be an error, or Rodenstock may have lightened something.
As for the performance, two samples aren't significant. At f16 they're equal, at 22 and 11 the "apo" version is more even, and either of them would be more than satisfactory for any purpose other than photographing resolution test charts.

[Ivan J. Eberle]

What I see from my 135mm Caltar IIN (Sironar N) looks better than what their test results would suggest. I'd say sample variation due to used lens condition. Their chart was also compiled over time using several cameras, IIRC.

[Leigh]

Also, confusingly he makes this statement about the APO Sironar-N 135mm even though the two lenses have different weights (185g vs. 170g):
"Also, for years, it was sold as the "plain" Sironar-N (no APO moniker). There was absolutely no design changes between the plain Sironar-N line and the current APO labeled line. This change was purely marketing hype."

The Sironar-N was an APO design according to the spec sheets, but was originally sold without that notation on the lens.

Apparently Schneider started selling their APO line and gained a marketing advantage, so Rodenstock re-labeled their product to include the APO designation.

This is not to be confused with the APO-Sironar-S lenses, which are very different designs (the 135mm weighs 240g).
I have most of the Apo-Sironar-S lenses, and they're superb.

I would guess the difference in weight between the two Thalmann lenses simply represents a reduction in the amount of metal used in the lens or shutter.

- Leigh

[altec2]

What I see from my 135mm Caltar IIN (Sironar N) looks better than what their test results would suggest. I'd say sample variation due to used lens condition. Their chart was also compiled over time using several cameras, IIRC.

That could be but I think it did pretty well in the tests. They both had really good consistent performance across the whole frame.

But i tend to think a one-off test of each lens is going to have some issues with variability so can't really rely on these for comparisons among very similar performers.

[Frank Petronio]

Since you're talking about used lenses regardless, you should consider condition first.

Then, if it is a really critical use, buy several lenses and test them. The sample variation and overall condition is going to be a great factor than the potential newer-versus-older-design's subtle performance differences.

[Ivan J. Eberle]

Slightly off-topic, but my Caltar IIN is stunningly sharp. The image circle difference between it and the APO Sironar S is so slight at this focal length that I've no desire to "upgrade".

[Adamphotoman]

All the manufacturers kept improving their products. This is as true for Rodenstock. They changed mounting methods and perhaps this partly accounts for weight differences. The Apo and non Apo versions will be the same basic design. And the newer offerings are better;
It depends on what you shoot and how you shoot it. I shoot a lot of art repro with a Betterlight digital back and with their viewfinder software. I set up using a custom Zigalign ZP4 and I can tell you that without these tools user error will degrade the comparison images.
These tools allow me to align the front standard to the rear standard or I should say the lens board to the film plane. You would be surprised that 0 detents are not as critical as one would hope or expect. Also I can align the film plane to the copy board. Only when this is done are the tests valid. These tests do mean something shooting paintings.

The digital back is very light hungry. Even with 900 watt North lights I am against the wall, (excuse the pun). This is why I seldom use the Apo Ronar. It needs to be shot at f22, which is out of the question when double polarization is needed. The Apo Sironar S allows me to shoot between f 8 and f8 1/2 where the Sironar convertible needs to shoot at f11 or f11 1/2. Both are extremely good.

The Caltar N-2 AKA Apo Sironar-N on the other hand is not as flat field. It needs to be shot at f11 1/2 to 16 for flat work and it falls short shooting a 20X30 painting. So in my work my clients can see the difference. Bob Solomon explains it better.

Quote:

Bob Salomon , Jun 24, 2008; 01:21 p.m.
Depends on what you shoot and how you shoot.
The S has a larger image circle and will be much sharper at the edges of the N's image circle. The S is corrected for 1:10 as compared to 1:20 for the N. That means that the S will perform optimally from infinity to 1:3 (tabletop) where the N will perform optimally down to 1:10. So if you do work from 1:10 to 1:3 the S is superior by quite a wide margin.
The S has less "harshness" while it has great sharpness. The N will appear more "harsh".
The color gradations of the S are finer then those of the N and the color saturation is slightly higher with the S. There is also more spatial depth and images appear more realistic when direct comparisons are made with the same focal lengths on the same film under then same lighting with the same exposure, lighting and processing.
A direct comparison of MTF curves shows much higher and straighter curves over a longer length for the S. Light falloff is substantially less and distortion with the S is much less then half of the N. Longitudinal color aberration with the S is also much lower then with the N.
So is there a meaningful difference? Absolutely! Will you see it? It depends on what you shoot, what type of camera movements you use, what you like and what you expect. But for critical users there is a visible and obvious difference.
That does not mean that the N is an inferior optic. It means that the S is a superlative one. But if one was to take a random image shot on the N and a random image shot on the S a viewer probably could not tell which was which. But if they are the same image at the same time you will see the difference.
And then there is Bokah.