Some tests rank-ordering a variety of classic and modern LF lenses

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Originally Posted by Joseph Kashi

Tested at 1:20, approximating my normal working distance and with flat field target perpendicular to lens axis. I was basically sorting out which lenses would work best for my own use and working style.

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Then why flat field?

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Originally Posted by Bob Salomon

Then why flat field?

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Sorry, perhaps I mis-phrased, apparently, in responding to what I thought was a question about testing for "field curvature". I used standard flat test targets and did not separately test for field curvature beyond what could be observed at the edges and corners.

Thanks for your effort, but unless you had a true optical bench system and an ability to keep film truly flat (which no ordinary holder provides), you've got some misleading variables inherently involved. There are quite a few other variables to contend with too; so alleged objectivity depends on how one defines the rules. You'll no doubt hear other such comments. But you obviously have plenty of lenses to choose from for you own preferred usage, and that's what counts. In large format work, the particular "rendering" or "look" a lens provides is often more important than nitpicking sharpness.

You have obviously put a great deal of effort into this and I applaud that. For portraiture I have done something similar with my lenses, this for babies, this for 20 somethings, this for 40 somethings and the Verito for 70 year olds and so on. Broadly speaking, descriptive personal preference and experience can be useful and certainly has validity. Well done.

Waiting for the resolution tests of Verito vs. Plasticca vs. Pinkham & Smith...

I rank them by age and sometimes sex of the sitter.
Verito at the far end, Kodak commercial for newborns , Heliars for twenty year olds, Kodak portrait or Imagon for thirty year olds, and the forty to fifty age group has to be individualized. Add 10 years for smokers. Pinkham are best overall.
Your mileage will vary.

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Originally Posted by Drew Wiley

...unless you had a true optical bench system and an ability to keep film truly flat (which no ordinary holder provides), you've got some misleading variables inherently involved. There are quite a few other variables to contend with too; so alleged objectivity depends on how one defines the rules...

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A reprise of Drew (who knows everything about everything) missing the point and not understanding that how LF lenses are used in real life is what's important. We've been through this -- painfully -- before:

https://www.largeformatphotography.i...=1#post1321449

At the end, I noted that everything Drew posts must be evaluated critically and, when appropriate, ignored.

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Originally Posted by Drew Wiley

...You'll no doubt hear other such comments...

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This is post #17. So far, yours is the only one.

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Originally Posted by Drew Wiley

...In large format work, the particular "rendering" or "look" a lens provides is often more important than nitpicking sharpness.

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In large format work, sharpness is often the driving factor motivating use of larger film. Wasting that potential on unsharp lenses is self defeating.

The reason that I took my personal results and started this thread was because I have noticed over the years that there's not much in the way of even basic comparative LF lens data on the web since Perez and Thalmann twenty years ago, although there's much strongly expressed opinion. I look forward to others providing more comprehensive and more precise data to the LF community in the future.

My broad take-away is that most modern-era lenses are more than good enough for practical use. Secondarily, reiterated comparative tests help us find subtle discrepancies such as small mis-alignments and improve the precision of our daily technique.

I used only rank-ordering because I made these tests as own-system practical tests similar to those Zone System tests that we made at MIT with Minor White many years ago. Yes, I have taken courses on experimental design when I was an undergraduate and then graduate student at MIT, I do understand how to design and conduct proper experiments, and can handle apparatus without breaking it. Living in a semi-rural part of Alaska 150 miles out of Anchorage, the nearest major city, I also understand the practicalities of use outside the lab.

Because these are practical usage tests, it seemed sensible to make them with the same equipment that would be used in the real world and with a similar (and verified) technique comparable to that I would use in the field. Were I publishing data in a peer-reviewed journal, the tests would have been done rather differently, of course, and I would have given numerical data as precise as I could make it. But, I'm not Roger Cicala and LensRentals, and, Roger's not testing LF lenses nor publishing LF lens MTF and other data. Also, to minimize copy to copy variation, Roger tries to test ten new copies of each lens, something not feasible for anyone in the LF community these days.

In the end, the reason that most of us even care about the relative quality of a lens is to make real-world photos. That's easiest to do by starting out with the sharpest, most contrasty lens possible - such lenses provide maximum information on the negative for later use/manipulation. If the lens is not a good one, then the information is never there and later analog/digital processing can't compensate for lost data.

... :)

There's a lot more to it than that. Yes, extreme sharpness might be the priority if I want to use the same lens in my 8x10 kit for roll film holder shots destined for a much higher degree of print magnification. But high contrast can sometimes be a detriment, especially to color transparency work. I'm sure the usual mosquito will bzzzz in to contradict anything I say, but whatever ..... "Quality" involves a lot of subjectives, which are very difficult to "rank" unless everybody thinks and composes photos in exactly the same manner; and thank goodness, we don't. Don't get me wrong; I once specialized in extremely sharp large Cibachrome prints. But that's just one side of the coin.