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  1. #41
    Poisson Du Jour's Avatar
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    Statements such as "contrasty lens" bandied around in forums (and dealers!) continually irk me. In years and years of printing to exhibition/gallery standard (Ilfochrome) using very high quality optics, I have not given much credit at all to a "contrasty lens", certainly not letting it sway judgement. If I end up with a lens that is "contrasty", you can bet your nellie the lens was considered for a very wide variety of factors, and that (contrast) wasn't one of them. Come to think of it now through reference, all of my Pentax 67 lenses are described as "sharp and contrasty". So? So...well, the images are very beautiful framed under spots (so are everybody else's MF prints), but there is more to it than "contrast" properties of a lens. Besides all of that, how is a lens judged or ascribed as "contrasty"? What is the quantification and qualification?
    .::Gary Rowan Higgins

    A comfort zone is a wonderful place. But nothing ever grows there.
    —Anon.






  2. #42

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    Quote Originally Posted by Poisson Du Jour View Post
    Statements such as "contrasty lens" bandied around in forums (and dealers!) continually irk me. In years and years of printing to exhibition/gallery standard (Ilfochrome) using very high quality optics, I have not given much credit at all to a "contrasty lens", certainly not letting it sway judgement. If I end up with a lens that is "contrasty", you can bet your nellie the lens was considered for a very wide variety of factors, and that (contrast) wasn't one of them. Come to think of it now through reference, all of my Pentax 67 lenses are described as "sharp and contrasty". So? So...well, the images are very beautiful framed under spots (so are everybody else's MF prints), but there is more to it than "contrast" properties of a lens. Besides all of that, how is a lens judged or ascribed as "contrasty"? What is the quantification and qualification?
    No veiling flare and good separation of tones in shadows and highlights.

    edit - If you are using "sharpness" as a criterion, you are considering contrast whether you know it or not. Sharpness and contrast are inextricably linked.
    Last edited by E. von Hoegh; 11-13-2012 at 04:51 PM. Click to view previous post history.

  3. #43
    Poisson Du Jour's Avatar
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    Quote Originally Posted by E. von Hoegh View Post
    No veiling flare and good separation of tones in shadows and highlights.

    edit - If you are using "sharpness" as a criterion, you are considering contrast whether you know it or not. Sharpness and contrast are inextricably linked.
    OK. I recall when I got the Pentax 67 lens that my only criterion was to "get some decent lenses" (I was a bit more specific starting out with the Canon kit many moons ago). Of course now I realise I got much, much more than I bargained for (I almost came home with a Hasselblad kit...) and I'm not complaining, certainly not about sharpness. It's good to have this contrasty lens subject out in the open, as too often a "contrasty lens" is judged as the only one somebody should buy without due and careful consideration to other factors (weight, ease of use, prime vs zoom, others...).
    .::Gary Rowan Higgins

    A comfort zone is a wonderful place. But nothing ever grows there.
    —Anon.






  4. #44

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    Quote Originally Posted by Poisson Du Jour View Post
    OK. I recall when I got the Pentax 67 lens that my only criterion was to "get some decent lenses" (I was a bit more specific starting out with the Canon kit many moons ago). Of course now I realise I got much, much more than I bargained for (I almost came home with a Hasselblad kit...) and I'm not complaining, certainly not about sharpness. It's good to have this contrasty lens subject out in the open, as too often a "contrasty lens" is judged as the only one somebody should buy without due and careful consideration to other factors (weight, ease of use, prime vs zoom, others...).
    Actually as long as you're talking about post WWII (coated) lenses, good contrast is more or less a given. Give a ca. 1950 135mm Graflex Optar (A Tessar type, renamed single coated Wollensak Raptar) a try, they're superb.

  5. #45
    Ian Grant's Avatar
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    Quote Originally Posted by cliveh View Post
    The lens is not the only thing that controls contrast, but I can't imagine ever buying a Leica Summar lens.
    Here you open another can of worms.

    An issue with some German lenses in the 1930's was the new optical glasses introduced, Leitz used them for the Summar, Zeiss for some redesigned Tessars and it went into some Novars. This glass ages badly whether it's atmospheric exposure to something I don't know but the result over the past few years is that some of these lenses have a distinct softness and despite the glass being clean & scratch free there's a very slight haziness which has a profound effect on contrast. The worst I've seen is on a Zeiss Ikonta with a Novar but I've seen it with a few Tessars and it's known in Summars. The new glasses were introduced to facilitate the production of faster lenses but they are significantly softer so more prone to issues like scratching during cleaning.

    There's probably other lenses affected but those are the 3 I've seen first hand, glasses changed again towards the end of the 1930's. The 135mm and 150mm Tessars were redesigned to fit the rimset Compur shutters around 1929/30 and again by 1938 when a more modern version of the f4.5 150mm appeared with T coating.

    So back to the Summar, many are soft, a great many are ruined with cleaning marks because the glass is so soft, but there are some that are OK. My first Summar came with a Leica IIA but I knew the lens was poor, that was 40 years ago. I replaced it with an Elmar. However knowing the issues with Summars I didn't buy another until I spotted a good one.

    The secret to checking is the reflections in a lens, you need good sharp reflections, no haze or diffusion particularly when that reflection itself is passing through other air glass surfaces.

    I've 4 CZJ Tessars (150mm & 165mm) sat in front of me 1913, 1926, 1932 and 1952/4, the worst is the 1930's version and I've had 3 that age before quite similar. My experience is the contrast difference between the earlier Tessars and the T coated Tessars is much closer than the 30's versions. Have to be careful here as not all Tessar FL's were reformulated with the new glass in the early 30's.

    Ian

  6. #46
    cliveh's Avatar
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    Thanks for that, as you mentioned many aspects I was nat aware of.

    “The contemplation of things as they are, without error or confusion, without substitution or imposture, is in itself a nobler thing than a whole harvest of invention”

    Francis Bacon

  7. #47
    Brian C. Miller's Avatar
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    Quote Originally Posted by RalphLambrecht View Post
    tne other question is:how do you want to measure and quantify lens contrast? how else would you compare lenses and their settings?
    A lens measurement would have to be conducted in a controlled environment with a test chart, and I'm sure that it would be similar to MTF testing ("evaluates a lens' performance, and its contrast sensitivity"). There are a number of free test charts available, and I would personally use a test target in a box like I saw one someone's web page. The photographer pointed the camera into the sun, and photographed the test target inside of a box. He did it with and without a lens hood.

    On the LFPF, we had a discussion about "bokeh," and I facetiously came up with the Drem Glasgnademeter and Leica Glasgeistometer. Later I came up with a set of possible measurements. I suppose things like flare and contrast control could be valid parts of that measurement.

  8. #48
    Klainmeister's Avatar
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    Neither linky is worky... =[
    K.S. Klain

  9. #49
    Ian Grant's Avatar
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    Quote Originally Posted by E. von Hoegh View Post
    Actually as long as you're talking about post WWII (coated) lenses, good contrast is more or less a given. Give a ca. 1950 135mm Graflex Optar (A Tessar type, renamed single coated Wollensak Raptar) a try, they're superb.
    We are in the 35mm sub forum but what's being said is still valid, and thats from experience.

    However there are exceptions like the Hoya lenses. I had a 28mm and flare was horrific, I had a Sigma 24mm before that and it wasn't much better.

    On the oyher hand LF lenses were always professional so coatings of all types were a league ahead.

    Ian

  10. #50

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    Quote Originally Posted by Ian Grant View Post
    We are in the 35mm sub forum but what's being said is still valid, and thats from experience.

    However there are exceptions like the Hoya lenses. I had a 28mm and flare was horrific, I had a Sigma 24mm before that and it wasn't much better.

    On the oyher hand LF lenses were always professional so coatings of all types were a league ahead.

    Ian
    Ian, what about the Hoya HMC filters? I have one 72mm (the only HMC I have) that's very good, I use it as a protective filter on a 20mm WA lens, as far as flare and reflections go it might as well not be there. Are they all this good or should I watch out?

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