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  1. #51
    gorbas's Avatar
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    Michael R, thank you very much for sharing this sensitometric curve. Very interesting results!! It made me very curious, so this morning I mixed fresh batch of BTTB with Kodalk and borax B baths. You are right, more testing is necessary.
    I'm one of the photographers that believes that 2 bath developers can deliver in "right situations" better results than any other traditional developer. In mid '80 I needed high energy developer for the project all done with available, tungsten light. It was impossible for me to buy Diafine or Tetenal Emofine so I found some two bath formula and made my own. It had 100g of Potassium carbonate in bath B. In it, I processed ORWO NP-7(movie stock, daddy of ORWO N-74), NP-27 and Kodak Tri-x. Grain wasn't a problem at all even on bigger enlargements. Later, when I had chance to use Neofin and Diafine I noticed they had way more energy then my own home brew. Last year I revisited that project and scan it. You can see results here:https://flic.kr/s/aHsjF21y2k

  2. #52

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    Thank you David and Michael for both of your help.

    As I stated before this is the first time I have had and issue with BTTB. I can only assume that somewhere I deviated from my normal routine without realizing it. Last night I developed a roll if Tri-X I had laying around and finally shot and the results were very good as I expected they should be. There was 6 stops between the side of the building I shot and the sky and I had no problems using normal development.

    I did mix a new batch before developing this roll. Which makes me wonder if some of bath b had contaminated bath a or if I had developed to many rolls in the last batch would either of those have been the cause of my problem? Assuming I had done everything else right?

    Bill,

    With some cropping the picture is fine looking however it loses some context.

    Again thanks for the help everyone.

  3. #53

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    As another example, attached are the results I got in a test with some more extreme variations in bath B, using D-23 for bath A. The dashed curves are the net densities after subtracting base+fog. Here again there was no change in contrast.

    It is important to note changing the agitation procedure in bath B can make a difference though. This is another issue with the directions often given for this type of development. More clarity is needed regarding differences in agitation in bath B, particularly given the great variety of formulas for bath B.
    Attached Thumbnails Attached Thumbnails D100.jpg  

  4. #54
    David Allen's Avatar
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    I did mix a new batch before developing this roll. Which makes me wonder if some of bath b had contaminated bath a or if I had developed to many rolls in the last batch would either of those have been the cause of my problem? Assuming I had done everything else right?
    Yes and yes and no. Contamination of Bath A by Bath B will cause you problems - specifically too much contrast or, if I understand the chemistry correctly, Bath A becoming a developer that advances the contrast too far and then Bath B becoming a redundant extra developer.

    Too many rolls through Bath B will not have caused your blown out highlights as putting too many rolls through Bath B will result in underdeveloped negatives/too little contrast. To make this clear, Bath A is capable of processing much more than 30 rolls. However, Bath B is ONLY capable of processing 12 rolls with predictable results. It is for this very reason that I mix 1L of Bath A and 2L of Bath B. I then process 12 films with Bath A and first batch of Bath B then proceed to process another 12 rolls with the same Bath A but with the second litre of Bath B. Bath A could probably work for at least another 24 rolls but why take the chance when the chemicals are so cheap??

    Best,

    David.
    www.deallen.de

  5. #55
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    Quote Originally Posted by David Allen View Post
    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.
    That actually lines up nicely with Michael R.'s latest plot which shows BTTB to be about a stop faster than D-23. With D-23 losing about two stops, this would lead to Delta 400 having 200 speed with BTTB. Let me say, though, that I am a bit puzzled about your statement that FX-37 gave you a speed loss ...
    Trying to be the best of whatever I am, even if what I am is no good.

  6. #56
    Bill Burk's Avatar
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    Quote Originally Posted by MrBrowning View Post
    With some cropping the picture is fine looking however it loses some context.

    Again thanks for the help everyone.
    MrBrowning,

    I could have figured... It sounds like you really wished the negative had been developed N-1 and you probably actually developed it to Normal... I'm surprised by the curves, because it appears the process can give normal contrast and a long straight line... Good advice all around, great thread to follow.

  7. #57
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    Let me say, though, that I am a bit puzzled about your statement that FX-37 gave you a speed loss ...
    There is a great difference between achieving full detail in the dark shadow areas (IF that is what you want) and achieving a good looking print if the shadows are unimportant to you. If the deep shadows are unimportant for how you want your photographs to look then your criteria in choosing a developer will be different. Crawley's FX-37 gives fantastic separation between the lower mid-tones and the bright highlights. If your way of working is such that the deep shadow areas are unimportant to you then Crawley's FX-37 is a great choice. It will give you an effective EI that is equal or more than the box speed. However, this is ONLY because you are choosing to ignore the deep shadows (which of course is fine as many photographers like this look and tailor their technique to suit). If you wish to record and use the dark shadow areas then you will need to give more exposure (including FX-37) and this may then give you problems with blown out highlights. Exactly what I meant with my previous post, achieving good shadow detail with most developers requires adequate exposure. If this is not your aim, then there are many developers, such as DDX, that will allow you to sacrifice shadow details but still give you a great negative in terms of the remaining tones.

    Horses for courses . . .

    Bests,

    David.
    www.dsallen.de

  8. #58

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    Quote Originally Posted by Rudeofus View Post
    That actually lines up nicely with Michael R.'s latest plot which shows BTTB to be about a stop faster than D-23. With D-23 losing about two stops, this would lead to Delta 400 having 200 speed with BTTB. .................
    But don't we generally find that setting meters to a film speed of half ISO about right in just about any normal developer (unless we're in a distinctly low light indoor situation)? I regard half ISO to be the real speed even with Xtol, Pyrocat-HD and, in the past, others.

  9. #59

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    Quote Originally Posted by David Allen View Post
    Yes and yes and no. Contamination of Bath A by Bath B will cause you problems - specifically too much contrast or, if I understand the chemistry correctly, Bath A becoming a developer that advances the contrast too far and then Bath B becoming a redundant extra developer.

    Too many rolls through Bath B will not have caused your blown out highlights as putting too many rolls through Bath B will result in underdeveloped negatives/too little contrast. To make this clear, Bath A is capable of processing much more than 30 rolls. However, Bath B is ONLY capable of processing 12 rolls with predictable results. It is for this very reason that I mix 1L of Bath A and 2L of Bath B. I then process 12 films with Bath A and first batch of Bath B then proceed to process another 12 rolls with the same Bath A but with the second litre of Bath B. Bath A could probably work for at least another 24 rolls but why take the chance when the chemicals are so cheap??

    Best,

    David.
    www.deallen.de
    Thanks. I highly doubt I developed more than 15 rolls in it. I had 13 marked down but looking at where I may have made a mistake I thought it was a possibility. As for contaminating A w/ B I doubt it happened but again there is a possibility.

    Thanks again.

  10. #60

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    Quote Originally Posted by Bill Burk View Post
    MrBrowning,

    I could have figured... It sounds like you really wished the negative had been developed N-1 and you probably actually developed it to Normal... I'm surprised by the curves, because it appears the process can give normal contrast and a long straight line... Good advice all around, great thread to follow.
    It's a developer that I really like using. I have had great results up until that one roll. From the results I've had in the past normal development has been fine. It just got me thinking if I ever needed it where should I start.

    And yes it has been a very good thread.



 

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