Modern vs Classic emulsions

Discussion in 'Black and White' started by gbuckles, Dec 8, 2005.

  1. I've noticed the term "modern emulsion" recently (specifically when
    referring to Acros 100) and really don't know what it means. Is it a
    matter of the look of a film or the physical make up of the film or
    both?

    Can someone please explain the differences between modern and
    classic emulsions and give some examples of both for 4x5 films?

    Thanks!
     
  2. Not sure if there is a universal answer to this. Some may consider Ilford FP4+ a modern emulsion compared to the older Ilford FP4.

    OR, some may consider the tabular grain films like Ilford Delta and Kodak TMAX 'modern' compared to Ilford FP4+ and Plus-X.

    ...and maybe I don't know what I am talking about.... ;)
     
  3. No, you are correct the Tabular grain is the big difference. T-max was the first, alough
    there are others likes like Acros.
     
  4. I am interested in see what people would call the entire Neopan line (SS, Acros, 400, 1600). Sorry for not answering your question.
     
  5. My history and my film manufacturing are probably a little off, but I'm sure I'll be corrected where wrong ;-)

    Basically, film emulsions can be looked at as two parts - the silver halides in the emulsion, and the way the emulsion is applied to the substrate. Both of these have changed over the years, sometimes together and sometimes not.

    In the "old" days there was Super XX (I'm not going back any farther than that). This was a large grain thick emulsion film. I believe the emulsion was applied as one thick layer. The thickness of the emulsion gave it interesting properties - developers took a while to soak into the emulsion and you could manipulate the hell out of it. It responded well to water bath developement, and stand development, etc.

    As time moved forward, there was continual effort to decrease the size of the grain, decrease the range of grain sizes, increase the real film speed, improve the physical properties of the film as a unit, decrease manufacturing costs, etc.

    In coating technology, manufacturers started making the coatings thiner, and often used multiple layers. In silver halide technology, things progressed to flat grain like Ilford's Delta and Kodak's Tmax films.

    The more modern films tend to have thinner total emulsion, but in multiple layers. The grain tends to be more uniform. And smaller. And more sensitive. Modern films tend to be more predictable in the darkroom, but don't respond as well to techniques like water bath development.

    Modern films too tend to have shorter toes and less shouldering. The straight line portion of the response curves are considerably longer as well.

    The difference between the old Super-XX and the current Tri-X is huge, for example. I have an old AA 20x16 inch print taken on 10x8 inch Super-XX film. The grain is very noticable, and it's only a 2x enlargement! I use the current Tri-X in 4x5. I've made 10x enlargements (about 50x40 inches) where you can't see the grain. Tonality seems different but comperable.

    To answer your question directly: The look of the film is tied heavily to the physical make up of the film. You can't easily separate them. In my mind, a modern emulsion is one that's currently available on the market. They are all good. I have no desire to retreat to the "good old days of Super-XX" at all.
     
  6. That's a very good explanation, but I can't help but wonder about the discontinued and lamented Verichrome Pan. It was a multicoated thin emulsion film, yet older than the hills. It's considered a classic, yet it seems to qualify as rather modern. The one I really miss is Ektapan. I believe it was multicoated and qualified as modern, but it was easily manipulated and certainly had "classic" tonal qualities. IMO, FP4+ is wonderful stuff, but definitely in the "modern" camp. The bottom line is still what you can get out of a film, not the label people put on it. Ok, I've probably just confused things again :)
     
  7. Gentlemen,

    Thanks for your insights. And Bruce, I appreciate your thoughtful answer on the subject.

    There is always something to learn and this is a great resource for the answers!
     
  8. There are a host of additional answers as well including hardener, synthetic substitutes for gelatin, and chemicals that can no longer be used in film, but which lent a particular 'character' to the image tone or whatever (in the eyes of the beholder).

    In any event, the old emulsions were not robust, hard to make, used toxic chemistry such as mercury and cadmium and the new ones eliminated the mercury and cadmium and changed over to a new hardener from the old standby, formaldehyde. They are made by a new automated process that allows much more repeatability from batch to batch for better uniformity.

    You may like or hate the new films, but environmentally they are so much more benign to manufacture and coat. As for tonality, they were designed from the start to give that long straight characteristic curve so that the photographer had more latitude to shoot with and got better pictures, but again, the acceptability of a given product is not a given. This is in the eye of the user.

    Ron Mowrey
     
  9. They way I always thought of it is the Tmax and Deltas are the moderns (Acros too being as new as it is); the HP5, FP4, PanF, Tri-X, Plus-X, Neopan 400...the "classics".

    Supposedly the modern emulsions are more sharp and less grainy for their speed than the classics, though some prefer the look of the classics (which for some reason are easier to develop, or more forgiving anyway).
     
  10. I find it interesting that the "old style" films are being sold as something better.

    In an old photography handbook I have, from the 60's, I think, the author raves about the new improved "thin" emulsions, and how much better they are....
     
  11. Hi Garth,
    I'sorry not to have known the Super XX, but the now sold as Adox effke made films at least bring some of the old stuff available today.
    Enlighting is their name system:
    cubic, vs. tabular (T or Delta) (Adox programm only contains the cubics)

    Single layer vs. Multilayer whereas the Single layers are the older emulsions like the original Adox from the 60s fka effke, the Multis said to be "very similar" to a known british manufacturers "classic" line.

    hetero vs mono-dispers is only interesting for their "micro" film, as all normal films are hetero-dispers, meaning they contain grains of various size.
    According to Mirko from fotoimpex, the Multilayer films have a big advantage in tolerance against overexposing. The single-layers have a roll of to the red side (which gives a characteristic colour representation).
    So actually I'd see three types of film.

    Try:
    an effke 100 aka Adox CHS 100 (acc. to my knowledge the "oldest" film available) vs.

    a PlusX or FP4 or Adox CHM 100 (is the latter available in 4x5?), thats what the kids of chromogenic and T-Crystal age call "classic" afaik vs.

    T-Max 100 or Delta 100 definitly not classic.

    Unfortunately I do not know, what the Acros is, still I like this film for 35mm (sometimes).

    Of course don't expect me to rate them as good or bad, for thats a matter of tast.

    Have fun,
    Martin
     
  12. I think classic vs modern emulsions has mostly to do with the thickness of the emulsion coating. Modern emulsions are thin emulsions.

    Essentially, back around 1954 Adox screwed up a batch of film by coating it with too much gelatin. They attempted to remove as much as they could, overcompensated, and notice that the film gave better sharpness and finer grain than existing films of the time. And so modern "thin" emulsions were born.

    So, effectively, all films introduced since that point (because the increases in pictorial quality imparted by thin emulsion coats were so dramatic) are modern emulsions. This includes films such as Tri-X, HP5+, Plus-X, etc. It also includes T-grain/Epitaxial grain emulsions like T-Max or Delta, though these were not introduced until more than 30 years after Adox's blunder.
     
  13. Dear Al,

    That's a fascinating story. I hesitate to impose upon you for a source or reference, not least because I am still trying to find my copy of the Ilford paper on monodisperse emulsions (tabular and epitaxial) but if you do have a source I'd be most obliged.

    Cheers,

    Roger
     
  14. I would like to hear a chemists perspective, like David Wood of DR5, weigh in on this. walt
     

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