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  1. #11

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    If everyone has a 20x24 why the heck are they so expensive?
    art is about managing compromise

  2. #12

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    How did this get off track so quickly? I, too, would like a choice in slow, fine-grain, small format films. I've never tried Efke 25, and I'm not sure I'm interested in working out exposure and processing protocol for something that may or may not survive; and I'm not sold on the quality control.

    So that leaves Pan F+. A fine film, and I'll gladly use it. But I'd really love to have a big stash of Agfapan 25, maybe Panatomic-X (though I never had much success with it) or a variety of other emulsions from which to choose.

    The market for slow, small format film is really small. That, I fear is the bottom line. Yes, modern emulsions are often as good or better than slower films of old. But with the advances made, it would be interesting to see someone take a whack at a great panchromatic 25 speed film.
    Honey, I promise no more searching eBay for cameras.

  3. #13

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    Quote Originally Posted by Earl Dunbar
    The market for slow, small format film is really small. That, I fear is the bottom line. Yes, modern emulsions are often as good or better than slower films of old. But with the advances made, it would be interesting to see someone take a whack at a great panchromatic 25 speed film.
    I understand your desire for the improvement, but I see a very good reason why no one wants to make an extremely fine grained b&w film at 25 speed.

    The last major increase in speed-to-grain ratio happened in 1990s. (Another technology, called two electron sensitization is beginning to be used in commercial products, which further doubles the speed of emulsions of same grain size.) At that point, they could make a 100-speed b&w film that exceeds the resolution of good, fixed focal-length lenses for 35mm format, and the grain could be already very fine. Fuji Acros and Kodak TMX are two films that give this level of excellent resolution, both with excellent fine grain and reciprocity failure properties. Since most people use zoom lenses, or shoot with suboptimal conditions (handholding, mirror vibration, film flatness issue, etc.), there is really no need for films to increase the resolution any further, unless there is a revolution in optical design. Color films, on the ohter hand, are always inferior to b&w films of the same speed in terms of resolution. Indeed, crystal sizes used in color emulsions are much larger than b&w of the same speed. So there is still lots of desire for color emulsions to improve.

    If there's any problem in this design spec issue, the camera optics are usually designed to meet the resolution of slow color films. When people argue the equivalent megapixels of 35mm format, they are of course assuming the typical MTF characteristics of a slow color film.

    So, as David said earlier, I also think using a bigger format is the real solution for improved image quality.

    My desire goes to more variety in enlarging papers... I think we have enough films.

  4. #14

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    Quote Originally Posted by avandesande
    If everyone has a 20x24 why the heck are they so expensive?
    They're sold by the ton.

  5. #15

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    Actually, a new slow ultra fine grained film has just been announced. SPUR, sorry that I don't have the URL to hand. This is the film that CZ used to get 400 lp/mm with.

  6. #16
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    "there is really no need for films to increase the resolution any further, unless there is a revolution in optical design." Ryuji.

    Look to the latest generation of lenses from Leica and Zeiss.

    Make a film with the color rendition of APX 100, but with superior acutance to TMX.

    Yes, and work on papers.

    I'll leave a light in the window.

    .
    "One of the painful things about our time is that those who feel certainty are stupid,
    and those with any imagination and understanding are filled with doubt and indecision"

    -Bertrand Russell

  7. #17

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    Don: Not sure I understand "color rendition of APX 100" reference. Are you asking for a colour film that has the resolution/grain characteristics of APX 100?

    Ryuji: I agree with DF regarding the lenses. I don't own any of those yet, though I have owned some Leica glass in the past. I do more handholding that I like, but I do use a tripod whenever I can, and will increase that habit when I get another one that better meets my needs.

    I've never used Acros and my only attempt at TMX didn't work so well. I should give them another try, though I've generally preferred the look of traditional films.

    I agree regarding papers. I wish the French producer of the original Zone VI Brilliant papers hadn't ceased production.
    Honey, I promise no more searching eBay for cameras.

  8. #18

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    I think that 100Tmax, Acros and Delta 100 are all nice films and we are lucky to have them. I am one of those dinosauers that uses only fixed focal lengths..I have never owned a zoom. I use a very heavy tripod made for 8x10 and use a rope from the center column and a foot pad to add to stability, mirror up etc.

    As nice as 100tmax is and irrespective of the finess of its grain and high contrast MTF characteristics it falls at least 20% behind Panatomix-X for low contrast MTF performance.

    Panatomic=X was my favorite b&w film in 120 roll film, 35mm and sheet film. kodak did this user no favor in discontinuing it.
    Claire (Ms Anne Thrope is in the darkroom)

  9. #19
    df cardwell's Avatar
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    Another dinosaur here. The new Leica lenses ( 35/1.4 ASPH, Apo-Summicrons, etc ) absolutely press the best films out there. And if the lens is used at a high speed and large aperture, it is apparent to see the revolution HAS happened. On a tripod, they are a revelation. The new Zeiss lenss seem... exciting.

    Earl: I'm wishing for a B&W film that sees color as did APX 100, which was its distinguishing characteristic. Sob.
    "One of the painful things about our time is that those who feel certainty are stupid,
    and those with any imagination and understanding are filled with doubt and indecision"

    -Bertrand Russell

  10. #20
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    There were basically 3 stages in B&W and color film evolution between the 70s and today. This would effectively allow a 200 speed film today to equal a 25 speed film of the early 60s.

    However, there are always tradeoffs in speed, grain and sharpness. For example, if you took an 800 film and doubled its speed using 2 electron sensitization to 1600, it may have worse keeping due to radiation (cosmic and heat), and so the tradeoff is to keep the same sensitivity to radiation at 800 speed and design for better grain. (this was hypothetical but appears to be the case for the new Portra 800).

    In color film, every layer is sensitive to only 1/3 of the spectrum range and therefore effectively, a given color grain has about 2 stops less speed than a comparable B&W emulsion. (just a rough analogy as turbidity and other factors enter into this equation).

    There are practical limits to what can be done then in either color or B&W. A 25 speed film made with today's technology should be extremely sharp and fine grained, but it actually is not as improved as one would expect from theory due to other factors such as the turbidity that I mentioned above. Overlapping grains and other physical phenomena tend to also degrade and limit a film from reaching its theoretical limit.

    So, in the final analysis, I think that an ISO 100 film is probably a compromise in overall keeping, speed, grain and sharpness giving us an optimum position for all of these that is equal to or even better than an ISO 25 film of 50 years ago. I just don't know for sure, and don't have the film to make the comparison test. Anyone out there make any tests? Panatomic X vs one of the new B&W ISO 100 or 200 films? Even an old Panatomic X pic reshot on a modern film and processed the same as the old film might help us all judge things better.

    We might come out of this feeling all the better when we see the results of a test like this. IDK, just a thought experiment.

    PE

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