Schneider vs Rodenstock - Is it relevant ?

[Mike Foster]

Hello everyone,

I know this may sound like a silly question but I really would appreciate some o pinions based on my arguments below.

I am just starting out in large format photography and am looking to get three l enses. The sharpness and overall image quality is of paramount importance to me, especially since I will shoot 6x9 almost exclusively, using a roll film back.

In particular, I am comparing Rodenstock and Schneider lenses and it seems that from the data of the lenses, the Rodenstock lenses are superior then their Schne ider counterparts.

For example the MTF curves of the Rodenstock Apo-Grandagon 45/4.5 are vastly sup erior to the Schneider Super Angulon XL 47/5.6. In fact the MTF curve for this p articular lens is so impressive that it pretty much matches the legendary Zeiss Biogon 38/4.5 for the Hasselblad SWC! And beats most other Zeiss wide angle lens es! Truly remarkable, if true!

Similarly the Grandagon-N 75/4.5 beats the Schneider Super Angulon XL 72/5.6. Ev en standard lenses seem to go Rodenstock?s way as far as the MTF curves are conc erned. Each Apo-Sironar-S beats its Schneider Apo Symmar counterpart and the che aper Sironar-N about matches it.

I know a lot of people will say that they are all the same ? performance wise th at is, even the G-Clarons! But then most people stop down to f22 or more. At suc h small apertures diffraction takes over and yes there indeed is very little or no difference at that aperture! In fact at f45 even a hundred year old lens will be as sharp as a modern one!

That really is not a fair way to judge a lens. One must stop down to the optimum aperture of each lens and not f22.

At f22 diffraction limits the resolution to around 60 lines per millimeter. I th ink f16 is fair since the diffraction limit is then 90 lines per millimeter. But again one must stop to the optimum aperture for that particular lens.

So what is the bottom line here? Are the Rodenstock lenses really that superior to the Schneider equivalents as the data suggests? Or are the MTF curves by Rode nstock rigged?

So which is better? Schneider or Rodenstock?

Thanks for reading and I look forward to some interesting posts!

[neil poulsen]

I'm curious. Where are you finding the MTF curves for Rodenstock? Is this from the Web, or do you have product literature? If on the Web, at what address can they be found?

[neil poulsen]

I'm curious. Where are you finding the MTF curves for Rodenstock? Is this from the web, or do you have product literature? If on the web, at what address can they be found?

[Trevor Crone]

Mike at the end of the day I feel there is very little to choose with regards to the sharpness between makes. I've long abandoned MTF curves etc. for I believe the majority of todays computer designed lenses are going to be first class for use in real world photography. If the final image is first rate I'm happy, remem ber the chain is only as strong as its weakest link, this of course could be any thing from the film holder to the enlarger/printer.

I use both Rodenstock and Schneider lenses for both 6x9cm and 4x5. I choose a pa rticular type/make which fits the bill for my photography, after choosing the fo cal length I look at its image circle (camera movements), weight and size (backp acking).

The only lens I was ever disapointed with was Schnider's 65 Super Angulon, it ha d poor edge sharpness (and I was only using it on 6x9 at the time). I exchanged the first one I purchased only to find the second one was the same. I sold it ev entually. But to balance things I use their 47XL and 110XL and find them to be f irst class with all the sharpness you could ask for. Regard,

[Glenn Kroeger]

Mike... some comments. First, remember that both companies MTF curves are theoretical not measured so the don't account for actual execution of the lens design. Manufacturing variations in polishing, centering and R.I. of glass will effect real MTF.

That said, the Apo-Grandagons really are spectacular. As impressive as the MTFs are, the proof is in shooting. I think the 55 is the sharpest LF lens I have used on 6x9. Also, on the Hasselblad web site, under Arc-Body lenses, you can see Apo-Grandagon and Grandagon- N 75 f/4.5 curves are 40 lp/mm which is important for roll film work. These lenses are quite spectacular at that spatial frequency as well.

Note that when looking at the MTF curves, the Apo-Symmars are tested at 1:infinity, or 1:10 while the Apo-Sironar curves are at 1:10 or 1:20 if I recall. Generally, the Rodenstock's seem to have slightly better on-axis performance while the Schneider curves are a bit flatter at ~3/4 of the image circle. My guess is that these differences are not significant in real lenses. The most difficult aspect in comparing for use on roll films is that Schneider doesn't publish curves for f/11 or f/16 and they don't publish chromatic aberation curves.

I am looking forward to comparing the new Super Symmar 80mm XL to the Grandagon-N 75mm f/4.5. On paper, it looks like the Grandagon-N is a better lens for roll-film, but given the on-film performance of the 110XL, I am curious to see if the paper results translate into reality.

[Doug Paramore]

Mike: This has nothing to do with MTF curves, but I have see a lot of lens seperation in Rodenstock lenses that are a few years old, including a 135mm camera lens and two enlarging lenses I own personally. I called a well respected LF technician to see about having the 135 fixed and was told it wasn't worth it. He also said that Rodenstock had a lot of problems with seperation. I hope the problem has been fixed on new lenses, but it is something to look into.

Regards,

[Larry Huppert]

As others have mentioned, both lens brands seem excellent in actual use. With that being said, it is also only fair to compare lenses with similar design parameters. As I remember, the Rodenstock 45mm lens doesn't cover 4x5 while the 47XL does (131mm vs. 166mm image circles). In a similar fashion, the Rodenstock 75mm has a 195mm IC while the Schneider 72XL has 226mm IC. If you need the coverage, no amount of MTF theoretical analysis can get you there.

[paul owen]

Just wanted to add my few pennies (cents!!) worth !! As has been already stated there is little or no difference between LF lenses these days, quality control and computer aided design have all but eradicated dodgy lenses. Everyone has their favourite lens and the majority will often purchase a lens after readin/hearing such recommendations. I once heard that the 100mm Apo Symmar (Schneider) was one of the sharpest lenses available for roll film. I got one and it was!! But only when stopped down to f22 was it okay for landscape (depth of field problems otherwise). You mention that MTF curves suggest that Rodenstock outperform Schneider, they may translate thus, but I no longer pay attention to these graphs. For LF image circle is of paramount performance and most LF lenses NEED to be stopped down to at least f22 (for landscape work) which makes the data included in the graphs pretty useless. Modern LF lenses outperform the film emulsions available anyhow and I doubt whether any one is able to tell which make of lens made a particular picture. Saying that I do own the 110XL and do believe the hype about its quality as I've seen it with my own eyes. In practical terms there are many more factors in LF photography that can spoil a good a good image...film not seated in holder, dust in holder, dodgy tripod, forgeting to remove darkslide, etc, etc,.... puts lens manufacturer into perspective I think!! Regards Paul

[Bob Salomon]

"I am looking forward to comparing the new Super Symmar 80mm XL to the Grandagon -N 75mm f/4.5. On paper, it looks like the Grandagon-N is a better lens for roll-fi lm, but given the on-film performance of the 110XL, I am curious to see if the paper results trans late into reality. "

Actually the best ones from Rodenstock for roll film are the Apo Sironar Digital series which are available from 35 up and most cover 6x12 so that would take care of all 45 roll formats except for 45 roll.

They are the most highly corrected lenses for small format in the Rodenstock lin e.

We can send spec sheets to anyone in the US who wants details.

[Michael S. Briggs]

My judgement is that the MTF curves for the Rodenstock Grandagon-N 75 mm f4.5 and the Schneider Super-Angulon XL 72 mm f5.6 are essentially tied. One important thing to realize is that the x-axis scales on the MTF curves published by the two makers are different: the x-axis of the Rodenstock curve (in their paper brochures) has units "image radius [mm]", while the Schneider graph has units of percent maximum image height. The Rodenstock graph goes from 0 to 101.2 mm, while the Schneider graph goes from 0 to 100%, with 100% being 113 mm. When comparing curves you have to be sure to compare the MTF values at the same radii in mm. For instance, 50 mm on the Rodenstock graph is 50 mm / 113 mm = 44% on the Schneider graph.

I read off the values for 10 lp/mm and f22 and the curves are very similar. For most values the Rodenstock MTF is slightly above the Schneider MTF, but there are radii where the Schneider MTF is higher. My guess is that the difference is not significant. The curves were calculated by different people, probably using different programs and perhaps slightly different approaches. It is likely that honest differences in the calculation could vary the results comparable to the differences between the curve. Additionally, there is the issue of how closely each manufactured lens matches the calculated MTF curves. (The Schneider graphs are described as calculated; I don't see any statement on this issue in the Rodenstock brochure.)

In short, Schneider and Rodenstock both make superb lenses. We are lucky to have them. Many of us tend to get obessive about lens quality.