"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"?
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.
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
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.
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
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
"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.
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?
---Scott
www.srosenberg.com
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.
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.
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