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  1. #81
    baachitraka's Avatar
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    @Michael: General question, May I ask what is your general opinion on two-bath developers?
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  2. #82
    Mainecoonmaniac's Avatar
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    2 bath developers piqued my interest. I have a couple questions. Ive heard older films have thicker emulsions and these formulas are also old so I'm wondering if that's the case, 2 bath developers don't behave the same on new emulsions? What's the difference between a 2 bath developer vs stand development at a high 1:100 dilution for an hour?

    I've had pretty good luck with stand development with HC-110 1:100 for an hour. I only develop with this method for high contrast shots. I've always exposed my film to avoid blowing out the highlights, but sometimes the I have to tame the contrast of the scene.
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
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  3. #83

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    baachitraka:

    Note the developers we've been discussing in this thread are not true two-bath developers. With a two-bath developer (such as Diafine) zero to minimal development occurs in bath A. Therefore you have relatively little control, but the sensitometric characteristics (good film speed, self-limiting contrast) compensate for the lack of control. The developers we've been discussing in this thread are different. Development occurs in both baths. This means you have control but you need to understand and use the controls properly (the way you would with any single bath developer). Further, I have limited my testing and discussion of these specifically to formulas with a single developing agent.

    Generalizations are problematic. In addition since I have not used these developers in my own photography, I can only discuss my test results. I can say a few things:

    1. From a sensitometric perspective, the results are different enough from single-bath development that they offer a potentially useful alternative, mostly for lower-than-normal contrast development

    2. The information out there about formulation, how they work, and how to use them, is mostly bad. I've posted a few things in this thread, but I had a more detailed thread about this some time ago

    3. The potential risk of uneven development should be kept in mind given the relatively short immersion times and the often unnecessarily high alkalinity of the second bath (which makes development very fast in the second bath). Test before you develop important negatives.

    4. Treat these developers the same way you'd treat any developer. That means be consistent with agitation, temperature etc.

    Hope this helps.

    Mainecoonmaniac: This kind of development is a different animal than stand or semi-stand. But stand is another one of those things - do people know what they're actually getting with a given film/developer combo? Is there compensation? Film speed? Is it giving reduced contrast? "blown highlights"? Etc.

    Michael
    Last edited by Michael R 1974; 06-24-2014 at 06:32 PM. Click to view previous post history.

  4. #84

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    Quote Originally Posted by Mainecoonmaniac View Post
    2 bath developers piqued my interest. I have a couple questions. Ive heard older films have thicker emulsions and these formulas are also old so I'm wondering if that's the case, 2 bath developers don't behave the same on new emulsions? What's the difference between a 2 bath developer vs stand development at a high 1:100 dilution for an hour?
    I understand your comment but the thin emulsion effect does not seem to occur...
    Quote Originally Posted by Xmas View Post
    Maybe but please see the HD's kindly provided by Michael, for his post bath experiments

    posts #45 & #53 earlier

    Not what Id have expected either
    maybe not everyone understands H&D curves is the other problem.
    They look like nice results...

  5. #85
    Mainecoonmaniac's Avatar
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    I might consider using Thorton's two bath developer

    Quote Originally Posted by Xmas View Post
    I understand your comment but the thin emulsion effect does not seem to occur...

    maybe not everyone understands H&D curves is the other problem.
    They look like nice results...
    This is going to be another tool I'll use. But I gotta test the film/developer combo before it's useful. Sure faster than stand development for an hour. I thinking the grain will be less due to the shorter development time.
    "Photography, like surfing, is an infinite process, a constantly evolving exploration of life."
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  6. #86

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    Just remember this type of development is not a substitute for other methods including stand. It has it's own unique sensitometric qualities, which will affect tone reproduction.

    With respect to granularity/graininess, this is a complex thing which depends on exposure, developer composition, pH (possibly), degree of development/density for a given amount of exposure, and time. So image structure and sensitometry are interrelated. For any given tone in the final print, a given two-bath process may produce higher or lower graininess than a stand-developed negative, etc. There isn't a simple answer. Different two-solution formulas could also give different results. There are many related formulas including Stoeckler, Leitz, Adams, Thornton etc.

  7. #87
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    2 bath developers piqued my interest. I have a couple questions. Ive heard older films have thicker emulsions and these formulas are also old so I'm wondering if that's the case, 2 bath developers don't behave the same on new emulsions?
    I have read this so often in discussions on the internet. The authors state with 'authority' that, because newer emulsions are thinner it MUST be the case (even Thornton made this assertion when discussing the Stöckler formula variant of two-bath developer). Of course it never seems to occur to anyone that this is an irrelevance for T-Grain emulsions as they weren't even around when Stöckler and Adams formulated their developers. I would have thought that the example photographs that I have posted in this thread clearly demonstrate that it works with today's film and delivers excellent results. It might be the case that it doesn't work the same as it did with older films but, nevertheless, it works fine with contemporary emulsions.

    maybe not everyone understands H&D curves is the other problem.
    This is exactly why I prefer to post actual photographs - other than providing me with very generalised comparative data H&D curves do not 'speak' to me in the way that looking at an actual photograph does. Whenever someone tells me something as a 'fact' I prefer to see examples so that I can judge for myself. For example, if you follow John Blakemore's advice you will have a very good chance of achieving images like his. I personally find Blakemore's printing style too soft for my taste. Therefore, having seen actual examples of his work (in exhibitions and books), I respect his philosophy of approach and recognise his technical command of the medium but would not want to produce my photographs in accord with the tonality that he prefers. Another example was the accepted 'fact' prevalent in the days when I used to be a member of a Photo Club (some 40 years ago) that you should always have a piece of old photo paper in the easel when you focus your negative otherwise you would not get a properly sharp image (due to the difference between negative to easel and negative to paper distance). Now anyone who has needed to correct converging verticals by tilting the easel will know that, at common apertures used for printing, there is a wide latitude within which everything will remain sharp (at least in practical terms).

    This is going to be another tool I'll use.
    'Tool' is a very good term to use. Every developer has its own characteristics and this is why one photographer will choose one and another photographer a completely different one - after all, there is no point using BTTB developer if you want your images to look like those of Mario Giacomelli.

    But I gotta test the film/developer combo before it's useful.
    Ultimately this is what all of us have to do. Sure, it is worth reading books and threads on the internet to get an idea of how a particular combo will work and to find what photographers whose work you like use themselves. Once you have seen a range of images using the combo that you are interested in using, then you need to test how it works for yourself.

    In terms of testing BTTB developer, if you look at my post #22 I would hope that there is enough information there to give you a good working starting point both in terms of exposure and the processing sequence. If you have your own testing sequence then use this as it will give you results comparable to other film/developer combos that you have previously tested. If not, you can find the sequence that I use here:

    http://www.apug.org/forums/forum37/1...-problems.html

    Best,

    David.
    www.dsallen.de

  8. #88

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    David, the problem is posting a print or a negative tells you very little unless there is something to compare it with. Even then, there are still all the variables involved in getting to the print besides the negative developer. Not to mention the printing preference of the photographer. I don't see any evidence of enhanced shadow or highlight detail in the posted examples vs what could be done with plain old D-76.

    Again, I am not saying these things because I have anything against two-solution development (see post #83). All I'm saying is when we talk about what a developer or process does, in comparison with other developers or processes, we need some kind of objective evidence. While H&D curves aren't exciting (nor are they perfect since they are subject to testing and measurement methods), and they certainly aren't necessary for making great negatives/prints, they can be useful when it comes to evaluating how things work relative to eachother. How else can we know what is really going on? Even in the case of BTTB, suppose it turns out you're actually overdeveloping with your process (ie giving expanded contrast to an already contrasty scene)? We simply don't know.

    Hope this clarifies a little.

  9. #89
    baachitraka's Avatar
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    Image Gradation comes to my mind, when considering how important H&D curves are. There is a chapter in 'Beyond The Zone System' book, which may give a perfect idea on this topic.
    OM-1n: Do I need to own a Leica?
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  10. #90

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    Curves are most useful for comparing processes and materials under controlled, constant conditions. When it comes to making pictures and prints, they aren't necessary. And in fact they can be problematic if one is unaware of the pitfalls. In the field, there are things like flare which change the effective curve. Further, densities measured with a densitometer (colour or B&W) can only approximate the effective printing density. Ultimately what is important is how your printing paper "sees" the negative. And tone reproduction never stops at the negative. The paper curve is as much a part of the process as that of the negative. So even if you start out by using curves to try to determine your EI, development times etc., they are only a starting point. You have to print negatives and fine tune everything that way - by eye. Don't simply rely on what Adams, Davis or anybody else says about target densities etc.

    If you get too caught up in plotting negative curves to determine your working methods without printing, you might end up being surprised at what you get when you print your supposedly perfectly calibrated negatives.
    Last edited by Michael R 1974; 06-25-2014 at 08:34 AM. Click to view previous post history.

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