210 APO-Symmar-L

[Scott Rosenberg]

hey guys...

is anyone using this lens? i've been able to find very little about them since their introduction, which is quite unlike the flurry of reports that usually surround the introduction of a new lens.

besides increasing the image circle to cover 8x10, did schneider make any other improvements to the optical performance of this lens over the venerable 210 APO-Symmar? with the increased coverage, this lens is, on paper, the equal of the Rodenstock APO-Sironar-S... is there any reason to think that this new design will outperform the 10+ year old Sironar-S design?

scott

[Steve Hamley]

Scott,

IIRC, they reformulated the glass without lead. Other than the unleaded glass and a bit more coverage, what little I've seen indicates performance is about the same. But let's face it; would anyone expect more than small incremental performance increases in a design as old as the plasmat?

BTW, Bob Salomon in his past posts alluded that the Apo Sironar-S has been incrementally improved throughout its run.

Steve

[Scott Rosenberg]

hey steve...
thanks for the info. i did find something on the littman site which stated basically that improvements in the manufacturing process reduced sample to sample variation considerably, in effect, making evey Symmar-L lens a 'select' lens.

from the site...
"... fabrication has really improved to a degree never seen before, variances from unit to unit still exist and are meaningful yet the consistency of the curve shows that the new lens could be slightly sharper wide open , and more consistently sharper at all distances than the previous model, it also proves the existence of an ideal scenario by showing that each element is quasi identical to the next which means that they can count with each piece of glass doing the intended job as opposed to the least desirable scenario which would be to make a front or rear element and then make the other to compensate or match, this was made possible by the incorporation of the latest computer technology into the lens grinding and polishing process.

Clearly this isn't only beneficial for those who buy many lenses, its optimum for those who buy just 1, in the old age lenses were very good when considered as a unit but inconsistent as individual elements and camera makers had to inspect hundreds to just " select" a few. The new L could be rated as " pre-selected".

[Donald Hutton]

C'mon Scott - buy one and tell.... BTW, I know you are looking for a Sironar-S - there are a couple around for $800.

[Scott Rosenberg]

hey don... gonna tip me off as to the whereabouts of these 210 APO-Sironar-S lenses?

[Scott Fleming]

I wish there was truly a way to KNOW the answer to this question AND so many other lens questions. It would be really nice if maybe at a convention of LF photographers everyone could bring their lenses ... all would be analysed ... and the results published. I'd pay to read the results. It would be worth a substantial amount of money actually. I'm sure this is impractical and would take a huge amount of time and be horrifically expensive.

I have serious doubts that the new invironmentally friendly glass is as good as the old leaded glass.

[Steve Hamley]

Scott,

I've been around "spin doctors" long enough to recognize potential marketing "smoke" when I see it, but I applaud Schneider for developing new LF lenses.

"... fabrication has really improved to a degree never seen before,...",

"... it also proves the existence of an ideal scenario by showing that each element is quasi identical to the next ...".

Phrases like these are really pretty meaningless although if I were buying I'd strongly consider these lenses. It would be interesting to know if these are Littman's comments or Schneider's and if Littman's what communication prompted him to say them. The comments imply their quality is significantly better than their competitor's quality (unlikely in this field). What they don't say is also important, for example they don't say they didn't have this degree of implied manufacturing quality in the last generation of "regular" Apo Symmars.

I think where you get significantly better image quality or performance is with significantly better designs. Now I'll believe that a Schneider Super Symmar XL has a leg up on Rodenstocks, Nikkors, Fujis because they don't seem to have have a competing design that seems to offer the coverage, weight, and other advertized advantages of the SS XL.

So let's have a lens with aspherical elements giving better edge performance, broad repro range, 90 degrees of coverage and a max f/6.8 aperture. Should be Dagor-like size wise with the alleged focus shift fixed and good up close. That's what I'd want for a next-gen "all purpose" lens instead of an incrementally better plasmat.

BTW "quasi identical" and phrases like "virtually the same" mean "different"!

Steve

[Scott Rosenberg]

here's a link to the article, steve:

http://www.littman45single.com/09wlsyb/whatlensshouldyouchoose.html

[Ted Harris]

As to Scott Flemming's comment ...... there was a time when every single lens that left the leitz factory was individually tested and the results of those tests, inclkuding the MTF curves for THAT lens, were included with the lens whne it left the factory. I can't remember when the practice stopped but it was likely sometime in the 1970's. Such attention to detail was, of course, one of the many reasons (pure snob appeal and marketing hype a few other non technical ones) why you usually paid so much more for Leitz optics than for other comperable optics.

You still get those kinds of individual tests and lenses matched lens to lens for commercial conema lenses where you frequently have a set of lenses specially made individually for a film. Of course, here we are talking single lenses that are priced higher than the total investment any of have in our entire LF system.

[Steve Hamley]

Scott,

Thanks for the link. I understand what Littman's saying now, and what he observes does indicate better tolerance control. However, we probably shouldn't read too much into the single fact that rangefinder cam curves are more consistent, because the relationship between more consistent rangefinder cam curves to any observable image quality is not self-evident (but we hope is true). It is encouraging because maybe there are less "duds" or even average lenses, and encouraging because of what we can get from Chris Perez' and Kerry Thallman's published tests.

(Ramble alert, with nothing to do about taking good pictures !!)

With respect to these tests and Scott F's comment, I think we don't really need to test LF lenses probably any more than Chris and Kerry have. What those tests tell me is 1) top-the-line vintage glass can be as sharp as new glass; 2) there's more sample variation between the same lenses of recent manufacture than we'd like to see; and finally and maybe even most importantly, 3) a good example of an old lens may be as good or better as any particular new one WRT resolution.

So I'd once again say what we need in a general purpose lens is not an improved plasmat, but a smaller, lighter lens with greater coverage and better edge performance - something comparable to the Schneider SS XL in manageable sizes from 135mm to say 360mm. So I'm less interested in a "big 4 plasmat shootout" (because it isn't going to tell me anything I don't already know) than I am a new and better performing general purpose lens design. At some point you've got to forget the vanishingly small difference in numbers and make photographs. Maybe Barbara Lowery of Cooke is listening!

Steve

[neil poulsen]

This is all very interesting, and Schneider and their customers will benefit from a reduction in variability lens to lens.

My question is whether or not the L-series lenses in time will exhibit the "Schneideritis" that was prevalent with so many of the Symmar-S lenses?

[Donald Hutton]

Well Neil

I guess you'll just have to buy a whole lot and wait for about 20 years then...

Seriously, it's a well documented issue to do with adhesives used by Schneider a long time ago. Schneider knows why it occurred. I have never seen an Apo Symmar with the condition and it has no effect on the optical charateristics of the lens. I hardly see why with new technology in adhesives and 20 years more manufacturing experience under the belt, the very latest lenses are going to suddenly develop "Schneideritis"... Too be honest element separation is a real optical roblem with lenses and I have not seen it on a modern Schneider, but have seen it on quite a few modern Rodenstocks... Now there's a problem to get your knickers in a knot about.

[paulr]

"With respect to these tests and Scott F's comment, I think we don't really need to test LF lenses probably any more than Chris and Kerry have. What those tests tell me is 1) top-the-line vintage glass can be as sharp as new glass; 2) there's more sample variation between the same lenses of recent manufacture than we'd like to see; and finally and maybe even most importantly, 3) a good example of an old lens may be as good or better as any particular new one WRT resolution."

I'm sorry, but chris and kerry's testing methods demonstrate that they've poured an enormous amount of time and energy into ... nothing. They simply don't understand optics beyond what was understood in the 1960s. Anyone flaunting resolution numbers as evidence of optical quality is just decades behind the current understanding of meaningful lens measurements. Their testing methods are essentially useless, as are their conclusions.

It is possible for vintage glass to be as sharp as modern glasss ... at a particular f stop, at a particular magnification, and on axis. maybe. But modern lenses are dramatically sharper overall, over a wider range of magnifications, and over a vastly wider angle of coverage. There are no two ways about it.

This doesn't mean that modern lenses are "better" ... if you prefer the subjective look of an old lens, then it's a better lens for you. But it's foolishness to think that that Schneider and Rodenstock and Nikon haven't figured out how to make sharper lenses over the last several decades.

We're clearly well into the era of diminishing returns. New lens generations seem to add less and less, and it's rarely an improvement in overall sharpness of the lens. It's qualities like the ones listed earlier ... sample-to-sample variation (one of the major improvements over vintage lenses), angle of coverage, sharpness at wide openings, and sometimes size and weight.

At any rate, anyone comparing lenses based on resolution really should do some research. You'll find that it's possible (common, actually) for a lower resolution lens to be sharper than a higher resolution lens. You might learn how to to read an MTF chart. And you'll see what spatial frequencies correspond to the ones your brain uses to perceive sharpness. Which is why a lens that produces high modulation (contrast) at 5-6 lp/mm (print resolution) but that has a low maximum resolution will appear much sharper than one that resolves many more lines per milimeter, but has lower modulation at 5-6 lp/mm. You'll figure out why those old resolution charts were used by the air force, and why they aren't of much use to anyone else.

On another note, Schneider actually tests all their lenses individually, by eye. They have highly trained guys who know how to interpret specialized test patterns that get projected through the lenses. They reaad them very fast, and for whatever reason are better at this than machines. This is the final quality control stage where the bad lenses get weeded out. I wouldn't be surprised if the other manufacturers did this too.

[Donald Hutton]

"I'm sorry, but chris and kerry's testing methods demonstrate that they've poured an enormous amount of time and energy into ... nothing. They simply don't understand optics beyond what was understood in the 1960s. Anyone flaunting resolution numbers as evidence of optical quality is just decades behind the current understanding of meaningful lens measurements. Their testing methods are essentially useless, as are their conclusions."

Well PaulR - they are subjective opinions backed by quite a bit of effort and research which they have been kind enough to share with the entire LF community - and while real genius like yourself may find this work completely useless, many haven't. Before berating their hugely generous effort and contribution, perhaps you could make a similar one? Or are your contributions restricted to cricital opinion?

[paulr]

I appreciate the generous spirit and the good faith of efforts like theirs, but at the same time I find it bizarre that they didn't do better research. The result is that they're providing extremely misleading information (worse in most cases than no information) to a whole lot of people. Granted, Chris and Kerry aren't prescribing dangerous drugs or leading people into cults, but they do seem to be providing information that more than a few people are basing big decisions on.

And I'm not touting myself as a genius, either. It doesn't take unusual gifts (I hope) to do some basic research on optics and human visual perception. An excellent book called Image Clarity came out fifteen years ago and was widely read by photographers and nerds alike. Since then there's been no end to the articles and research available on the web. It should take just a few mouse clicks to point you to well researched articles that demonstrated the uselessness of resolution numbers when evaluating lenses.

My contribution may well be limited to a critical opinion--but I'd be happier knowing it encouraged at least someone to examine other evidence before being misled by bad research, and spending a lot of hard-earned money on the wrong thing for the wrong reasons.

[Scott Rosenberg]

paul... would you mind sharing what's in your bag? you clearly have a different method of selecting lenses from the population-at-large, and as such i for one would be interested to hear which conclusions your approach led to.

[Kerry L. Thalmann]

Paul,

While I undestand exactly what you are saying, and agree with a lot of it, you have jumped to some erroneous conclusions based and a whole string of false assumptions.

First, and foremost, whenever I discuss the results of the lens tests Chris and I conducted, I always start out by saying that people should not read too much into the results. I am always sure to point out that resolution is only one component of lens perfomance. Here's a quote from a post I made in the rec.photo.equipment.large-format newsgroup several years ago:

"For the lenses we tested, we measured resolution only. This is just one factor involved in the performance of a lens. It is the easiest to measure, and one that people seem to get excited about. But, contrast, resistance to flare, rendetion of out of focus areas, color rendition, coverage, etc. are also important (and not covered in our modest tests). "

I am also diligent in pointing out the flaws and limitations of our test methods. I encourage people NOT to take our results as gospel truth. As is evident from Schneider's claims, sample-to-sample variation is still an issue even in this modern day and age. Heck, even the focal length varies from sample to sample. It is not surprising that the performance would also vary by a small amount from the design target.

But modern lenses are dramatically sharper overall, over a wider range of magnifications, and over a vastly wider angle of coverage. There are no two ways about it.

Define "modern lens". Would a Super Angulon be considered a "modern lens"? Afterall, the f8 Super Angulon lens dates from 1954. Most large format lenses in current production were designed 20 - 30 years ago. The Fujinon C series dates from 1982. Most of the large format Nikkors date from the late 1970s. Even relativley new designs like the APO-Sironar-S and APO Grandagon are well over 10 years old. So, "modern" is a relative term. Some would say lenses that were designed with the aid of a computer would qualify as modern. That puts us back to the 1950s. Other would consider only multicoated lenses modern. That puts is back to the 1970s. And as I said even if you only consider current offerings, many date from the late 1970s or early 1980s.

They simply don't understand optics beyond what was understood in the 1960s.

Another false assumption.

Anyone flaunting resolution numbers as evidence of optical quality is just decades behind the current understanding of meaningful lens measurements.

No one is flaunting anything. The numbers are just that, numbers. We claim they are nothing more than what they are.

But it's foolishness to think that that Schneider and Rodenstock and Nikon haven't figured out how to make sharper lenses over the last several decades.

Another false assumption. Show me one quote where I've ever said anything to the contrary. In fact, if you will actually take the time to look through our results, you'll see that most of the really outstanding results (corner to corner) are for the most modern lenses. Occasionally an older lens will do well, usually in the center, but if you study the results you will see lenses like the 90mm Nikkor SW (a design that dates to the late 1970s, BTW), the 110mm Super Symmar XL, the 240mm Fujinon A, etc. tend to have the best overall test results. This is no coindidence. BTW, it's been two decades since Nikon has designed any new large format lenses. So, anything they've learned in the last 20 years is irrelevant to this discussion.

It's qualities like the ones listed earlier ... sample-to-sample variation (one of the major improvements over vintage lenses)

Bingo! This, in fact, was the genesis for our little lens testing chore. If you'd taken the time to do a little research, you'd know this all started as a search to find the "best" compact wide angle for backpacking with a 4x5. I started with five 90mm Angulons. As the tests results show, sample to sample variation was all over the map. It kind of grew from there. I have stated repeatedly that we were only really interested in the relative resolution of the specific lenses we tested. I have never encouraged anyone to accept our results as absolute or universal. In fact, quite the opposite.

You might learn how to to read an MTF chart.

Yet another false assumption. I am quite capable of reading an MTF chart - when I can get my hands on one. Problem is, I have NEVER seen a single MTF chart for ANY Nikkor or Fujinon large format lens. Nor can I locate one on any number of discontinued, pervious generation lenses. Sure, I'd love to have an MTF chart for every lens I own or am considering purchasing, but they simply aren't attainable for the majority of large format lenses other than current Schneider and Rodenstock models. And even then, they are based on calculated data, not measured performance of any particular lens. I have neither the time, equipment, nor money to do actual MTF measurements on my lenses. If you'd like to perform these measurements, I'd be happy to loan you every large format lenses I own for this purpose.

On another note, Schneider actually tests all their lenses individually, by eye. They have highly trained guys who know how to interpret specialized test patterns that get projected through the lenses. They reaad them very fast, and for whatever reason are better at this than machines. This is the final quality control stage where the bad lenses get weeded out. I wouldn't be surprised if the other manufacturers did this too.

Hardly a new method. This is exactly how Linhof tested their rebadged lenses going back to the 1950s (most recently using a Siemens Star tester). I have an old copy of Photo Techniques International from the early 1960s showing a Linhof employee performing these tests.

I appreciate the generous spirit and the good faith of efforts like theirs, but at the same time I find it bizarre that they didn't do better research.

Another false assumption.

An excellent book called Image Clarity came out fifteen years ago and was widely read by photographers and nerds alike.

I did read Image Clarity by John B. Williams back in 1998 - when Chris and I were performing our tests (I even mentioned it in a post in r.p.e.l-f I made at the time). A bit dry, but very informative.

It should take just a few mouse clicks to point you to well researched articles that demonstrated the uselessness of resolution numbers when evaluating lenses.

I would disagree that resolution numbers are useless. They are certainly not the only factor to consider, but I also don't think they should totally discounted.

The result is that they're providing extremely misleading information (worse in most cases than no information) to a whole lot of people. Granted, Chris and Kerry aren't prescribing dangerous drugs or leading people into cults, but they do seem to be providing information that more than a few people are basing big decisions on.

Don't you think you're being just a tad melodramatic here? Seriously, they are just numbers. We have never recommended anyone make any life altering decisions based on our results. I do not hesitate to recommend lenses I have found to be outstanding performers, but they are based on actual use, and not just test chart results. Please see the Future Classics (http://www.thalmann.com/largeformat/future.htm) section of my web site for several examples of lenses I recommend. If you disagree with any of these recommendations, or find them misleading in any way, please state your case, share your first hand opinions on the lens I discussed and offer alternative recommendations.

My contribution may well be limited to a critical opinion--but I'd be happier knowing it encouraged at least someone to examine other evidence before being misled by bad research, and spending a lot of hard-earned money on the wrong thing for the wrong reasons.

Could you please site one example where I've encouraged anyone to do otherwise. Seriously, you accuse me of bad research when you've obviously done very little yourself prior to attacking me here. Your conclusions about me and what I lenses I do and do not recommend are totally erroneous and based entirely on a series of false assumtions. I don't mind people disagreeing with me, in fact I encourage it. Dissenting opinions make for interesting debate. However, in the future please base your arguments on what I actually say, not on assumptions you choose to make. You have read far to much into our simple test results (exactly what you were cautioning others not to do). Again, they are just resolution numbers for a few lenses we happened to have access to. They are not a buyer's guide. They are not a guarantee that any lens you buy will be as good, better or worse than any other lens you may or may not buy. They are simply the resolution numbers, based on a very small sample size, within the limits of our test methdology, for a few lenses. They were never intended to be anything more. Ultimately, it is up to the individual to consider all available data (and opinions), and their own specific needs and budget, when buying any lens. To do otherwise is foolhardy and not recommended. Not now, not ever.

Kerry

[Scott Rosenberg]

i know i'm about to jump into a tank with much larger fish, put if i may interject.

Paul, i agree with you in that the tests Kerry and Chris performed should not be taken as absolutes. i know nothing of their testing procedures, but if they each made independent contributions to the table, then those tests should be taken separately. to further subdivide, only measurements made on the same day developed at the same time and analyzed by the same person under the same conditions can be taken as relative results. all others are useful only as an absolute metric for the specific lens returning the numbers and CAN NOT be taken as a relative metric to all other lenses tested. some of these sources of variation can be controlled with repeatability, but there was never any mention of the repeatability of the entire exercise, as such there is some bit of statistical uncertainty in what data is returned.

however, bear in mind that Kerry and Chris NEVER suggested that the results of a lens they physically tested, say a Fuji 240-A, had any implications to a Fuji 240-A they did not test. in fact, at the end of their table, they state as much...

"This is at best a relative (not absolute) comparison between these lenses. Kerry and I are simply looking for the Pick of the Litter."

they then go on to list many of the uncontrolled sources of variation, allowing the viewer to come to their own conclusions. i hardly think it's fair to blame Kerry or Chris if people misinterpret what they've put out there, particularly when they clearly list the limitations of their findings. they state very clearly that this entire study was so that Chris and Kerry could select the best of the lenses they had available to them. applying their findings to lenses they did not test is something they specifically cautioned against, but if people continue to do so, that certainly is not something you can fault Kerry and Chris for.

their measurements make for an interesting study, and i for one am certainly appreciative that they put them (and themselves, apparently) out there for public scrutiny. how others choose to use the data, especially after the authors cited the limitations or their findings, is out of their hands.

scott

[Steve Hamley]

Boy did I open a can of worms. My apologies to Kerry; I know how long it takes to compile a carefully composed post this long.

But most people are still focusing on only one of several relevant lens issues (as Kerry and I have noted in other posts). For example, I know a published photographer who uses a Caltar II-E because it's flare resistant, and he chooses it over all others. How many of the lens cognoscenti would be caught dead with this "economy" lens on their Linhofs, Ebonys, and Arcas? I understand why he likes it if the reports are accurate; my 135mm Apo Sironar-S is bad about producing an iris ghost when pointed toward the light, and I have a multicoated Fuji 240-A that's ruined several pics with an out-of-frame sun. I'd gladly trade some resolution for high flare resistance.

We've also migrated to more saturated films and contrastier lenses to the point several people I know keep Astia and color neg film on hand because high sat films and lenses can't handle the tonal range of many scenes. I have noted that the vintage glass does render with less saturation, so maybe the contrast and saturation of modern lenses isn't as good a thing as some folks seem to believe (although controlling contrast and saturation by film choice is probably the better way).

Anyway, Kerry's and Chris' tests told me what I needed to know about resolution, and I also know that performance in the field under real conditions is probably more important, although no one ever seems to discuss it. Keep an open mind, question the "truths', and take more pictures!

Steve

[paulr]

Kerry,

I'm sorry for what must seem like a behind-the-back attack. Most of my points are directed toward anyone who is using resolution numbers to base comparisons on. Comments like 'doing some research might teach you to read an mtf chart' were not directed at you specifically, but at anyone who hasn't done research beyond looking at resolution tests.

I maintain a degree of perplexedness at why you would bother to do resolution tests (in the old fashioned mode of listing maximum resolution numbers). The problem with these tests in not that they're incomplete--you could argue that any objective test is incomplete in any number of ways. The problem is that they're completely misleading. In other words, there is essentially no correlation between masimum resolution numbers and subjective sharpness or clarity of a lens. In many cases there is actually an inverse relationship.

Here are some reasons:
While there is no real objective measure for resolution, it usually taken to mean the maximum frequency of line pairs (on a 100% contrast target) that can be discerned by eye. Different people have different thresholds for what they can see, but with one person doing all the tests there is at least a degree of consistency. That being said, what the tester is probably seeing at those high frequencies is faint renderings of the target lines, at perhaps 2% or 3% contrast.

Image detail rendered at sub-5% contrast at very high frequencies contributes nothing to a sense of sharpness or clarity. It in fact looks like haze in an actual photograph. Also consider that very little detail in real world subjects is differentiated by contrasts even approaching 100%. A tree branch against the sky might be 70% contrast; this you could expect to disappear completely if smallest enough to register at the highest tested resolution of a lens.

Our eyes establish sharpness using a number of cues, but by far the most important is the contrast (edge definition) of detail in the 5-6 lp/mm range (on a print). This sounds like low resoloution, but these details are actually quite fine.
Consider also that you cannot see detail finer than 11-12 lp/mm. Even with perfectly corrected vision, the rod and cone density of the human retina places a hard limit on this. This has been tested over and over again by different labs for different purposes*

This is why when you evaluate a lens using an mtf chart, you need to keep in mind what size enlargements you're most likely to make (not to mention other factors, like what magnifications, what f-stops, and what severity of camera movements--most mtf charts show these variables, at least somewhat).

A lens that produces excellent contrast in the 5-6lp/mm range (whatever that may translate to on the negative or chrome) will often do so at the expense of contrast at higher frequencies. Such a lens will test poorly in a maximum resolution test. Likewise, a lens that produces astonishing maximum resolution numbers will frequently produce lower contrast in the key 5-5 lp/mm frequencies. Prints won't look sharp. There will be tons of detail there that can mined from the depths with sharpening filters, but the overall look of the lens will be flat and dull. This is not actually a hypothetical situation; it's actually a standard compromise that lens designers make. They need to choose between a long, shallow sloping mtf curve (emphasizing high frequencies at low contrast--which would look good in resolution tests) or a flatter mtf curve with a sharper dropoff (emphasizing the frequencies that will make most prints look good, but that will typically score middling results on a resolution test).

This is why I think that for most purposes, resolution charts like the ones in question are actually useless. They're more than incomplete; they actually provide information that's going to be misleading to most people.

*It is true that you can see individual features that are smaller than, say 1/24 mm wide. With high enough contrast you can see much smaller features (you could probably see a 1 micron hole in black material with a bright enough light shining through it). But this isn't resolution. You are not "resolving" something that small. You are in fact seeing a blur of light that is much larger than the actual object. The test for resolution is how close things can be together before they blur into one.

[Donald Hutton]

"A lens that produces excellent contrast in the 5-6lp/mm range (whatever that may translate to on the negative or chrome) will often do so at the expense of contrast at higher frequencies."

Instead of a statement - how about some evidence of this? Please substantiate this with some proof (even if your testing methods are not completely sound). How often is "often"?

[paulr]

Don,
that's of course the key question, and I wouldn't expect anyone to just take my word for it. And certainly not to trust any testing that I claimed as my own. There's no remotely accurate way to do homegrown mtf testing (which is one of the reasons that it still remains a mystery to so many people).

I first learned about it from a friend who was a technician at Schneider. I then saw the idea illustrated in the Williams book on Image Clarity. Later I saw evidence of it comparing mtf curves of lenses designed for different purposes (process lenses vs. general purpose lenses vs. aerial photography lenses.

I'm going to try to find good evidence of this phenomenon on the web to post here.

[Kerry L. Thalmann]

Apologies for the previous long-winded diatribe (and the hopefully, kindler, gentler one that follows). It was late when I posted it and I probably should have slept on it before launching a response to Paul's cititcism. For those who don't wish to read my previous response, here's a quick summary:

Our lens test results were never meant to be the last word on anything. Intitially, the tests were conducted for our own benefit. When we decided to share the results, the intent was that they serve as a stimulus for further discussion/investigation. Anyone who reads more into them than that is missing the point entirely and reading far too much into the posted results.

Ironically, if Paul and I were to actually sit down and discuss the results, we'd probably find we are in agreement on most of the major points. Specifically, the subject of sample-to-sample variation. That's one thing we noticed very early in our testing. In general, this variation is much greater in older lenses than current models. This is not surprising given general improvements in manufacturing and quality control techniques. This is definitely one area where "modern" lenses have an advantage. You are much less likely to get a lemon made in the last 10 - 20 years than one made back in the 1940s, 1950s or 1960s. That should not be a surprise. What some people may not know is further improvements are still possible in this area. That Schneider continues to address this underscores the significance of this issue. I applaud their efforts.

This is also one reason I usually recommend current or recent generation lenses to those starting out - if they can afford them. Some of the best bargains out there in terms of bang-for-the-buck are previous generation used lenses from the major manufacturers (Schneider Symmar S MC and APO Symmar, Fujinon W multicoated and Rodenstock Sironar-N or Caltar II-N). I do occasionally recommend a few specific older single coated lenses for people who have very specific needs (i.e. a very small, compact lens for backpacking, or for people with a very limited budget). Even in those cases, I tend to recommend something newer like a 150mm f6.3 Fujinon W - which is a great little lens that can often be found for less than $200.

Let's face it, we all have slightly different needs and checkbooks. While I generally recemmend the best of the best (see Future Classics reference above), not everybody can afford the latest and greatest. For those people who can't, it's encouraging to know that great images can still be made with classic and affordable lenses (like the little 203mm Kodak Ektar). Heck, I can't even decide what's the best lens for my needs. I personally am using three different lenses in the 200mm - 210mm range these days - and I like them all for different reasons. My main 210mm is an APO Symmar that is a lovely lens. However, it's a bit on the big and heavy side for backpacking. In that situation, I use a 200mm Nikkor M that's a little gem. It lacks the coverage of the 210mm APO Symmar, but within it's more modest image circle, performance is excellent. Finally, I'm currently using a 210mm Graphic-Kowa for 4x10. It's overall performance may slightly lag the newer, multicoated APO Symmar, but it's still a great performer that has even more coverage than the APO Symmar and is less than 1/2 the size and weight.

Sorry for steering this thread even further off topic. I'm just trying to underscore that there are several things to consider when buying a lens.

Scott, back to your original question. I have not had the opportunity to test the new APO-Symmar-L series against the Rodenstock APO-Sironar-S. From the MTF curves, the performance of the APO-Symmar-L looks to be very similar to the previous generation APO Symmar - which is quite outstanding. I did test my 210mm APO Symmar against a 210mm APO-Sironar-S and decided to keep the APO Symmar for reasons that had nothing to do with performance. They were both quite excellent. So, choosing between the two would be like splitting hairs. The slightly greater coverage of the APO-Sironar-S (316mm IC vs. 305mm) was not enough to make a difference in my application (primarily 4x5 color landscape photography). The size and weight was comparable (same filter size, within 10g on my scale). My decision came down to pure economics. I knew I could get more for the APO-Sironar-S than the APO Symmar. It was a newer lens in better cosmetic condition with the original box. So, I sold it and kept the APO Symmar with no regrets. Had the economic considerations been equal, I'm sure I would have been just as satisfied with the APO-Sironar-S.

Kerry

[paulr]

Another good question brought up by Kerry is "what constitutes a modern lens?"
I can't think of a hard and fast rule here, but in general I'd say that multicoated lenses are modern, uncoated lenses are old, and single coated lenses are somewhere in between. I believe most lens lines started multicoating in the 1970s.

There is probably no other single refinement that has made a such a difference in measured and seen lens quality. And I believe it's the main reason that people who like vintage lenses like them--they don't like the harder, multicoated lens look. There's a kind of glow that you can get with an old lens that's actually a product of flair. It can be very beautiful for certain kinds of effects, although labcoat wearing technician would consider it to be the product of a flaw.

[Kerry L. Thalmann]

I maintain a degree of perplexedness at why you would bother to do resolution tests (in the old fashioned mode of listing maximum resolution numbers).

The reason was simple: to weed out the dogs among a lot of similar lenses. Specifically, I was looking for a very tiny, compact wide angle for backpacking with my 4x5. We started with several Angulons, and handful of wide angle Congos and a couple WF Ektars. Given that other characteristics are likely to be similar within one brand/type of lens, we identified which ones were most likely to offer the best performance. In other words, the "best" 90mm Angulon, the "best" 90mm WA Congo and the "best" 100mm WF Ektar (where "best" = the candidate most likely to yield the best overall performance). These lenses were then subjected to further real world testing (I actually took some real pictures with them). Based on these results, I decided to keep one of the little 90mm WA Congos. It was the only one of the three that is multicoated, it's smaller lighter and comes in a better shutter(Copal 0) than the WF Ektar, and produced colors that were a much better match for my other modern, multicoated lenses than the Angulon (which had a sinificantly cooler color palette).

There's no remotely accurate way to do homegrown mtf testing

Exactly. Back in the 1990s, the Siemens Star Tester cost 500,000 DM. And, in lieue of manufacturer provided MTF charts from Nikon, Fuji, previous generation Rodenstock and Schneider, etc. what are we to do?

I can't think of a hard and fast rule here, but in general I'd say that multicoated lenses are modern, uncoated lenses are old, and single coated lenses are somewhere in between. I believe most lens lines started multicoating in the 1970s.

Most large format manufacturers started multicoating their lenses in the late 1970s or early 1980s. Of course, several lenses (Fujinon L Series, Schndeider Xenars and C Clarons) remained single coated up to their end of line in the 1990s. And then, there are lenses like the Super Angulons and the Symmar S series that began life single coated, but later transitioned to multicoating. FWIW, we did not test any uncoated lenses. Everything we tested was either single coated or multicoated. I personally prefer multicoated lenses, but that's a matter of personal preference.

Kerry

[Steve Hamley]

Paul,

It isn't all flare, some of it is uncorrected abberations! But lens making is a science while picture making is an art. I don't think you can say pictures made with multicoated lenses are any better than those made with uncoated or single coated lenses by virtue of their technical attributes. Different, yes.

Just for the record, my 4x5 camera pack contains the latest or near latest multicoated lenses in modern shutters, and this is exactly what I tell people to do if they only have 1 lens or 1 set of lenses. I carry vintage glass for 4x5 when I have a reason to do so or I'm shooting out of the truck and the extra weight/space isn't an issue. But when you start talking about carrying an 8x10, you'll find there are some very compelling reasons to use vintage glass - just compare the weight and sizes of a 6-1/2" WA Dagor to a 150mm Schneider SS XL.

Old glass isn't for everyone and I'm careful when someone asks me about the old glass I sometimes use. If you don't buy carefully, you can certainly end up with a bunch of hazy, moldy glass in a shutter (or barrel) full of congealed grease with no retaining ring or lenscaps that won't use current filters (a.k.a., "moneypit").

Steve

[paulr]

"It isn't all flare, some of it is uncorrected abberations! But lens making is a science while picture making is an art. I don't think you can say pictures made with multicoated lenses are any better than those made with uncoated or single coated lenses by virtue of their technical attributes. Different, yes."

i'm sure you're right that some of it's abberations, and there are probably factors we know nothing about. and i completely agree they are simply different from one another, and not better/worse. in terms of sharpness, or the objective qualities technicians use, there's a clear heirarchy, but that may or may not have anything to do with any one person's esthetic. i use modern lenses because they suit my work, but i love the look of old lenses when they're used in a way that takes advantage of their character.

[Scott Rosenberg]

paul, i'm sure i'm not the only curious one...

i use modern lenses because they suit my work, but i love the look of old lenses when they're used in a way that takes advantage of their character.

which modern lenses do you use?

[Jan Virtanen]

I have a 210 mm APO symmar L, i dont have much experience with large format lenses
as i have only two and those i have only used. But the 210mm seems to control flare
pretty well, i shot some night scenes with it, 5x7 format.

[paulr]

I have a 210mm apo symmar s and a 120mm super angulon, both from the mid 90s.

I did a ton of research before buying these lenses, because I was dirt poor and because I was a total geek. I chose these lenses because they seemed incrementally better than other modern options, for my purposes. If I did studio work, I might have chosen rodenstock.

but here's the punchline. after using these lenses for years, and comparing the results to my friends' results, i think i would have done just as well to buy whichever brand was on sale. for one thing, i noticed that there was a huge difference between the sharpness of my sharpest images vs. my more typical images. which meant that most of the time, i wasn't even coming close to the potential of the lens. some of the culprits were focus (i mostly photograph urban landscapes, and in most cases there isn't just one plane of focus), wind, and user error (mine). in light of these major factors, quibbling over which $1000 high tech piece of glass to choose seems like a silly pursuit. I also spent some time looking at friends' work. One shoots 4x5 with nikkor optics, the other 5x7 with rodenstock. comparing our best results, with a loupe or with a critical grain focuser, i can honestly say there were no significant differences. all these modern lenses are really, really good ... much better than the conditions that i usually use them in.

there's a world of difference between these results and the ones that i'd gotten with older lenses. i've used older uncoated kodak lenses from the 40s and 50s, and single coated caltars from i don't know when, and a few other borrowed lenses from the same era. They did some beautiful things, but were not capable of putting the kind of sharp edges on things that the modern lenses did.

i also had an interesting experience with a friend's lenses for his 8x10. he uses old (gigantic) apo process lenses, like the kodak copying ektanons and one by goerz and one by zeiss. They produce undbelievable contact pritnt, both in terms of tone and sharpness. but a look with a loupe shows very little resolution (meaning, extreme falloff of modulation at higher frequencies). these lenses are an example of high modulation at critical frequencies, but low maximum resolution. they would make crappy looking enlargements. but they were gorgeous for contact prints.

[Donald Hutton]

"You'll find that it's possible (common, actually) for a lower resolution lens to be sharper than a higher resolution lens." Paul I actually just don't believe that this applies to modern LF optics (which after all is what we are discussing here) - please can you provide some examples or some source material I can go and have a look at.
Also:

"Which is why a lens that produces high modulation (contrast) at 5-6 lp/mm (print resolution) but that has a low maximum resolution will appear much sharper than one that resolves many more lines per milimeter, but has lower modulation at 5-6 lp/mm." Can you explain this a little more clearly - Are we talking about contact printing here, or are we making some very huge assumptions about enlargment size. Once again, I've yet to see a modern LF optic which produces low modulation at print resolution (I'm presuming contact print - so no enlargement factor) but whose resolving ability is very high. My experience and (just about everyone else's too) seems to indicate that they are all practically indentical at print resolution (which is just a nothing sort of measure when no enlargement factor is used). I cannot believe that any modern lens is going to appear "much sharper" than any other at print resolution.

I recently tested 10 modern 150mm lenses to answer my curiosity around which lens would be most suitable for my puposes. I shoot architecture and some landscapes - color and black and white. I was interested in which lens would produce the best print (so there are a whole lot of variables in there). Percieved sharpness and tonal graduations are probably the key factors. Perceived sharpness includes modulation and resolution in a very "layman" kind of way. I shot a test chart and a real world 3-D subject (subject in both B&W and color). I'm aware of the limitations of the test chart. I was going to follow Norman Koren's methodology, but rightly figured that for what I wanted to deduce, the real world subject supported by the test chart would tell me all I needed to know. What did suprise me is that the test target (just the rez bars from the USAF chart shot centrally and with an edge target in the frame) actually produced the same results as the real world subject across the board. Were there significant differences: not really - one of the 10 was quite weak (I'm guessing it was a bit of a lemon lens). The rest would all have produced results which were not discernable in B&W prints under close examination below a 6X enlargement (24X30 from a 4X5 negative). To split hairs on the top 5, you would need very big enlargements (over 10X). Basically, this really validated Kerry and Chris' testing for me in a real sense - what is contained therein needs understanding in it's application, but it is an extremely useful resource, even for the completely uninformed and ignorant. Anyone not wishing to spend a lot of time testing or being geeky would be very well served to just blindly follow the results - and spend that time making photographs instead.

[paulr]

"Can you explain this a little more clearly - Are we talking about contact
printing here, or are we making some very huge assumptions about enlargment size"

we're by necessity making some major assumptions about enlargement size ... which is something that you have to do unless you're looking at an mtf chart. this is one of the problems with the resolution number game ... it doesn't tell you anything about how the lens
will perform at different enlargement sizes. the nicest contact prints i've ever seen came from old process lenses like zeiss apo-tessars and kodak copying ektanons. these lenses produced incredible contrast at 5lp/mm or so. but they were very poor performers if measured by maximum visible resolution. enlargements would look soft.

your experience that the differences between the modern lenses were miniscule (not counting the lemmon) mirror my own experiences. These lenses are very, very good. If you do want to split hairs for whatever reason, or test some older lenses, one of the challenges is testing that mimics the whole range of conditions under which you might use the lens. if you do just one kind of thing (shooting at infinity, at f16, with few movements, for exapmple) then a simple test like the one you did can work really well.

Otherwise, as a look at almost any group of mtf charts for similar lenses will show you, performance at on axis does not reliably predict performance off axis; performance at 1:10 does not reliably predict performance at infinity; performance at f22 does not reliably predict performance wide open. And performance at 20lp/mm does not reliably predict performance at 5lp/mm. Doing any kind of real-world test, or even air force test target test, that takes these variables into account would take days for each lens and would give you a pile of data that's very hard to interpret or to compare. an mtf chart puts it all on one page in a standardized (almost) format.

With modern lenses, almost all of this is about splitting hairs, as you suggested. In most real world situations many other factors influencing image quality are likely to be more important. for the amount of money these lenses cost, though, some hair-splitting might be warranted. I chose my lenses over the number 2 choice because it seemed like it would be slightly better at infinity. If I shot in the studio, the choice would have been reversed. I doubt the real difference would actually be visible in most photographs, but who knows? For $900, I wanted some comfort. A resolution test would not have given this information. It would very likely have led me to the opposite conclusion, depending on how it was done.

Of course, a stumbling block is that mtf charts aren't available for all lenses, especially old ones. This is unfortunate, because older designs are even more likely to exhibit wildly different abilities under different circumstances. My solution was simple: narrow down the field to companies that provide mtf charts. More and more companies do it now, so it's not such a big deal. At any rate, I'm less likely to trust a manufacturer that even today declines to publish this information. For me, being able to narrow the field down, and to do all my comparisons with a few sheets of paper in front of me, actually felt like a lot less geekery and time wasting than trying to go out and do my own tests. And the information is categorically more useful than anything achievable with homegrown tests using resolution charts, or other tests based incorrect assumptions about lens quality.