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  1. #41

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    Quote Originally Posted by David Allen View Post
    I think this is the gist of this thread that is being missed. The OP stated that he was happy using BTTB developer but wanted to understand other people's experience with it.
    You have not read the OPs first three posts or forgotten: the OP had one specific question, which you may well know the answer to but you prefer to dissemble instead.

    I'll answer your other queries properly if you decide to help the OP fair exchange

  2. #42
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    Back to OP question: the best way to have N- development with this kind of developer is with borax in B bath as few other people already suggested. When I tried BTTB first time I found that Kodalk is just too active for my taste. Unfortunately I did not try to lower amount of Kodalk in bath B next time.
    And to keep topic of Two bath developers going, does anybody is using two bath developers with bigger capacity tanks, like paterson 5 or 8 - 35mm rolls with out using "dip & dunk method" (open the tank in darkroom and transfer reels to another pre filled tank with solution B).

  3. #43

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    Quote Originally Posted by David Allen View Post
    Sorry Michael, nothing personal meant but I personally have never found densitometer readings, characteristic curves, photographs of Macbeth tests, etc very stimulating - good images is another thing altogether because I look at good photographs with great relish. Of course the developer that you use and gives you the results that you want is the 'best' developer and we are very lucky with our medium in that there are so many combinations out their to suit every taste. As to theory, well Ansel Adams was pretty shaky in many areas quite often getting things quite wrong but, whether you personally like his work or not, the technical prowess and technique cannot be argued with.

    However, to suggest that there has been no good testing of Two-Bath developers in general and Barry Thornton's in particular is a misnomer. True there may not have been much in the way of scientific lab-based tests but there are hundreds of thousands of real world practical tests (I prefer to call them successful images that the photographer has chosen to print) that demonstrate that BTTW works exceptionally well for the people who want the results that it gives. In my case it has, for many many years, consistently delivered negatives that suit my image making. It has also been a winner was many of the people I have taught. Not always, of course, because each student has different ideas about what they want. If you want images that look like Daido Moriyama or Anders Petersen the BTTW is not going to get you very far and this is but one of many examples of needing to choose the correct developer for the results that you want to achieve.

    I think the key point here is that the OP was asking for advice on how to improve results using BTTW developer. In the main what the OP got was advice not to use this developer which then inevitably leads everyone else to speak up for their own preferred developer. What would be really great is if photographers with experience of BTTW developer could contribute with their own experiences with a clear explanation of how they use it, why the continue to use it or, if after really working a lot with it, they chose to work with a different developer.

    Bests,

    David
    www.dsallen.de
    David, I hear what you're saying and I agree in the end all that matters is that you get negatives you like. However if you read my posts in this thread carefully you'll notice I didn't try to get OP to switch developers, stop using BTTB etc. I only tried to suggest some controls which might be more effective with BTTB-type developers vs what Thornton suggested regarding the alkali.

    With respect to H&D curves etc, the anti-curve view comes up quite often on APUG. I get it. And I also agree you don't need sensitometric testing to make good negatives. However it is also important to remember that without objective data and careful, controlled testing, you can't say much about what is actually happening. You can only guess - and most people would be surprised at how far off they are. You can get used to the negatives you make, and make excellent prints from them either way because the materials and processes we have at our disposal are so flexible. But that doesn't mean we're making the negatives we think we're making. And that is why when photographers write books about technique, they should simply tell you how they do it and stop there. When they go beyond that and tell you how their techniques work, what the chemistry is doing, etc, they are often wrong. This applies to some pretty big names.

    So I'm definitely not telling anyone to buy a densitometer - and indeed even if you have one you might still be technically wrong. You don't need that kind of data to learn to make good negatives and great prints. All I'm saying is people should be more careful about how much they speculate regarding how the materials and chemicals are working and what is actually going on (for example when someone tells you to use xg borax instead of xg metaborate in bath B to lower contrast). For that you need careful testing and data. Without it, there is no way of knowing whether the information is good or bad, and you can't draw meaningful conclusions.

  4. #44

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    Quote Originally Posted by gorbas View Post
    Back to OP question: the best way to have N- development with this kind of developer is with borax in B bath as few other people already suggested. When I tried BTTB first time I found that Kodalk is just too active for my taste. Unfortunately I did not try to lower amount of Kodalk in bath B next time.
    And to keep topic of Two bath developers going, does anybody is using two bath developers with bigger capacity tanks, like paterson 5 or 8 - 35mm rolls with out using "dip & dunk method" (open the tank in darkroom and transfer reels to another pre filled tank with solution B).
    Barry's site says sodium metaborate 12gm/l is that Borax or kodalk?
    Yes I use 5 and 8 tanks for processing pour out bath A into stock bottle with funnel, pour in bath B borax...
    True the bottom film gets longer in solution but I vary by leaving in bath B to completion, and I was using D25.
    note do have two tanks moving eight wet reels in dark way to difficult
    Last edited by Xmas; 06-20-2014 at 11:48 AM. Click to view previous post history. Reason: added fotnote

  5. #45

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    Sodium metaborate is Kodalk. Borax is sodium tetraborate.

    Just to give one example of some test results, attached is an extract from a series of experiments I did (documented in a thread somewhere on here) on divided Metol-sulfite/alkali development. I was trying to test the various variables/controls with the aim of clarifying at least a few things, since there is so much conflicting information around regarding times, agitation in each bath, etc. There are many variables.

    In this particular test (using the Stoeckler fine grain formula where bath A is similar to Thornton, D-23, etc., the idea was to keep everything constant except the alkali in the second bath. Note these were sensitometric tests so I did not evaluate differences in image structure.
    Attached Thumbnails Attached Thumbnails fig2.jpg  

  6. #46

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    Quote Originally Posted by Michael R 1974 View Post
    Sodium metaborate is Kodalk. Borax is sodium tetraborate.

    Just to give one example of some test results, attached is an extract from a series of experiments I did (documented in a thread somewhere on here) on divided Metol-sulfite/alkali development. I was trying to test the various variables/controls with the aim of clarifying at least a few things, since there is so much conflicting information around regarding times, agitation in each bath, etc. There are many variables.

    In this particular test (using the Stoeckler fine grain formula where bath A is similar to Thornton, D-23, etc., the idea was to keep everything constant except the alkali in the second bath. Note these were sensitometric tests so I did not evaluate differences in image structure.
    Hi Michael

    Thanks twice over the H&D was more than useful.

    Noel

  7. #47

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    Quote Originally Posted by Michael R 1974 View Post
    Sodium metaborate is Kodalk. Borax is sodium tetraborate.

    Just to give one example of some test results, attached is an extract from a series of experiments I did (documented in a thread somewhere on here) on divided Metol-sulfite/alkali development. I was trying to test the various variables/controls with the aim of clarifying at least a few things, since there is so much conflicting information around regarding times, agitation in each bath, etc. There are many variables.

    In this particular test (using the Stoeckler fine grain formula where bath A is similar to Thornton, D-23, etc., the idea was to keep everything constant except the alkali in the second bath. Note these were sensitometric tests so I did not evaluate differences in image structure.
    Thanks Michael. It looks like a useful speed enhancement as a result of the second bath. I realise that it's a higher contrast but not grossly so. Would I be correct in thinking that the speed enhancement is much more than longer development just in bath A?

  8. #48
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    You have not read the OPs first three posts or forgotten: the OP had one specific question, which you may well know the answer to but you prefer to dissemble instead.

    I'll answer your other queries properly if you decide to help the OP fair exchange
    Dear Xmas,

    Perhaps you have missed my earlier post #22? - I would regard that as a pretty comprehensive answer covering exposure, the different Bath B solutions and the processing sequence that I use. I could not add more without seeing the original negative.

    And that is why when photographers write books about technique, they should simply tell you how they do it and stop there. When they go beyond that and tell you how their techniques work, what the chemistry is doing, etc, they are often wrong. This applies to some pretty big names.
    Hi Michael,

    I couldn't agree more. Too often one reads that X developer is fantastic because of Y theory without a detailed practical explanation of how the photographer actually uses it (i.e. explaining what film speed is used, how exposure is determined, whether plastic, metal or deep tanks are used, type of agitation given, etc, etc).

    It is for this reason why I set out in my post #22 how I do things (given that OP is getting blown out highlights and I do not). I have no in-depth knowledge of the chemistry but know that when I teach people my exposure/processing system and they follow it without making changes, they achieve comparable results to mine. This is also why I set out my processing sequence together with two images explaining how I metered them in the hope that the OP could compare what he does to what I do to identify why he is getting blown out highlights - something I have never observed with either my own negatives or other people that I know who use BTTB developer.

    Bests,

    David.
    www.dsallen.de

  9. #49
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    Quote Originally Posted by john_s View Post
    Thanks Michael. It looks like a useful speed enhancement as a result of the second bath. I realise that it's a higher contrast but not grossly so. Would I be correct in thinking that the speed enhancement is much more than longer development just in bath A?
    Longer development in bath A will give you the results of regular D-23 development - which means a speed loss of about two stops (I'm ready to get crucified by D-23 disciples for stating this ). If you look at David Allen's statements, he puts lowest shadow detail into Zone III, not Zone I, which tells me he also loses about two stops (correct me if I'm wrong, David).

    We have seen from Michael R.'s low contrast dev threads, that underdevelopment gives much reduced film speed, so I would not over interpret his chart with regard to "Bath A only" development.
    Trying to be the best of whatever I am, even if what I am is no good.

  10. #50
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    If you look at David Allen's statements, he puts lowest shadow detail into Zone III, not Zone I, which tells me he also loses about two stops (correct me if I'm wrong, David).
    Not quite Rudeofus as 'a loss of two stops (when using BTTB developer)' depends on whether the box speed is appropriate for one's working methods, the subject matter and also how this compares to other developers. Previously, I have used D76, HC110, a different replenishing two-bath, Perceptol, Crawley's FX-37 and Michael Maunder's Cellar-Stellar. With the exception of Cellar-Stellar, I found that various films processed in all of these developers required more exposure (than indicated by the box speed) IF one wished to retain good shadow detail. I used Cellar-Stellar for a while, when I was working on a project with a Leica M3, in combination with Pan-F (this was in the early 1980s) and my tests indicated a personal EI of 80. The Cellar-Stellar negatives looked rather 'thin' but retained very good shadow detail and printed very easily on Grade III Argenta paper using a Leitz Focomat with condensors

    I have undertaken tests to determine the correct EI for Delta 400 in my Mamiya 7 with 65mm lens, my meter (Weston V), my metering method and developed in BTTB developer for 5 minutes in each bath. My personal EI is 200.

    My metering method is to meter the area where I wish to retain some shadow detail (note: not the darkest shadow in the scene) and then place this on Zone III:

    In the first image on post #22 which is in daylight, I metered the shadow area at the bottom of the chimney and placed this on Zone III. I chose not to retain detail in the doorway at bottom right nor in the reflection of the scaffolding at top right.

    In the second image on post #22 which is at night, I metered the shadow area of the tree which is slightly to the left of the centre of the image and placed this on Zone III.

    Of course this explains my methodology but doesn't give other photographers much idea of how many stops I 'loose' compared to what they do. To give some idea here is a quick explanation:

    In Berlin, on a bright sunny day, there is often a big difference between a grey plastered wall / dirty brickwork in shadow and a white wall in full sunlight (as in the first photograph). Here I will typically find that placing the shadow area where I wish to retain detail on Zone III will result in the white highlight falling on Zone X. I do not worry about this wide subject brightness as experience has shown me that BTTB developer will retain detail throughout. As an indication to other photographers, my typical exposure (such as in the first photograph) will range between 1/125 @ f16.5 to 1/60 @ f16.5 depending upon how much shadow detail I wish to retain (usually quite a lot). In an image containing a lot of shadow area the previous exposures will still apply. However, if the scene comprises of very very small areas of shadow (where it does not make sense to retain detail) and lots of mid-tones and highlights the exposure is more likely to be 1/250 @f16.5.

    Hope that explains everything.

    David.
    www.dsallen.de

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