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  1. #21
    gainer's Avatar
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    In case it's too difficult to figure out, here's a formula for a liquid FX55 part B with very long shelf life.

    1 gram phenidone
    10 grams TEA (it's liquid, but easier to measure by weight in such small amounts.)
    12 grams ascorbic acid, either L- or D-
    Glycol or glycerol to make 100 ml.
    Glycerol is more viscous.

    Use 10 ml of the above in place of 0.1 grams phenidone and 1.3 grams of sodium ascorbate.
    Gadget Gainer

  2. #22

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    Quote Originally Posted by Keith Tapscott. View Post
    Which issue of `Amateur Photographer` is this article?
    I find the dilution confusing, as Part `A` is diluted 1+9, but how much of solution `B` is added?
    Is the formula for solution `B` also to make 1 litre of stock solution? Can the potassium carbonate be replaced with sodium carbonate? If so, how much would be required?
    Keith It's the latest issue. You raise some good points. Part A makes 1 ltr stock to which part B is added. However my tank only needs 250ml at a 1:9 dilution. So do I add the same quantities, as Mr Crawley suggests to 1 litre, to 250mls. My assumption was that I do as I assume that part B remains the same whether you use the whole litre or only a part of a litre. In effect it is part B to say 25mls of stock at 1:9 to make up my 250 mls

    However an assumption is all that it is. If part B was proportional to liquid used then I think that Mr Crawley would have mentioned it. In fact at a further dilution of part A at 1:9 the phenidone quantity would drop to a very small level - impossible to measure by most normal scales.

    So until someone who knows better tells me, I'll continue to assume that part B is a fixed amount to be added each time to whatever portion of the 1 litre needed at a 1:9 dilution to make up a sufficient developer quantity

    However this brings me on to the second issue. Does 1:9 mean 1 part A and 9 parts water( usually expressed as 1+9) or is it a total of 9 parts so it is 1 part A and eight parts water?

    A wrong assumption on both counts above could presumably be disastrous.

    Anyone enlighten me?

    Thanks

    pentaxuser

  3. #23
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    Quote Originally Posted by gainer View Post
    In case it's too difficult to figure out, here's a formula for a liquid FX55 part B with very long shelf life.

    1 gram phenidone
    10 grams TEA (it's liquid, but easier to measure by weight in such small amounts.)
    12 grams ascorbic acid, either L- or D-
    Glycol or glycerol to make 100 ml.
    Glycerol is more viscous.

    Use 10 ml of the above in place of 0.1 grams phenidone and 1.3 grams of sodium ascorbate.
    This looks like the right way to do it. My previous post only referred to the OP's post and the directions given there. I have used your PC tea and still have it on the shelf, it seems to be really stable. I was going to do this last night but the Gin drink and my easy chair derailed the effort!! I have lots of duplicate sheets so can afford to waste a few....EC

  4. #24
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    Quote Originally Posted by pentaxuser View Post
    Keith It's the latest issue. You raise some good points. Part A makes 1 ltr stock to which part B is added. However my tank only needs 250ml at a 1:9 dilution. So do I add the same quantities, as Mr Crawley suggests to 1 litre, to 250mls. My assumption was that I do as I assume that part B remains the same whether you use the whole litre or only a part of a litre. In effect it is part B to say 25mls of stock at 1:9 to make up my 250 mls

    However an assumption is all that it is. If part B was proportional to liquid used then I think that Mr Crawley would have mentioned it. In fact at a further dilution of part A at 1:9 the phenidone quantity would drop to a very small level - impossible to measure by most normal scales.

    So until someone who knows better tells me, I'll continue to assume that part B is a fixed amount to be added each time to whatever portion of the 1 litre needed at a 1:9 dilution to make up a sufficient developer quantity

    However this brings me on to the second issue. Does 1:9 mean 1 part A and 9 parts water( usually expressed as 1+9) or is it a total of 9 parts so it is 1 part A and eight parts water?

    A wrong assumption on both counts above could presumably be disastrous.

    Anyone enlighten me?

    Thanks

    pentaxuser
    I think something got lost in translation. It would not make Crawley Sense to have a variable amount of part A and a fixed amount of the powdered B part. The translation of 1:9 is 1 part A and 9 parts water to make 10 parts total. The part that was left out IMO is that the powdered chemicals are to be added to 1 liter of the working solution. If you don't need a liter, throw the excess down the drain. It's too cheap to bother with weighing. Either that, or make the suggested B solution with ascorbic acid, phenidone, TEA and Glycol or gylcerol and measure it out with a calibrated medicine dropper. How would you expect to get the same results as the next guy if your concentration of developing agents was twice his simply because you only needed half as much? You don't even know if he is developing more or less film per liter than you do.

    Simply put, IMO what the Master meant to say is to take 100 ml part A, mix it with 900 ml water and add 0.1 grams of phenidone and 1.3 grams of sodium ascorbate.

    Let's consider another proposition. In the face of so much buffering, will it really make a difference if you use ascorbic acid instead of sodium ascorbate? If not, then the TEA can be left out and a B solution of 1 gram of phenidone and 12 grams of ascorbic acid in glycol or glycerol used. As I review what I've been preaching, I see that 12 grams of ascorbic may not dissolve in 100 ml of glycol. If not, use 200 ml and double the dose to 20 ml/l of working A.
    Gadget Gainer

  5. #25
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    Remember ratios in arithmetic. Stock:water::1:9. "Stock is to water as 1 is to 9" is the way to read that shorthand, as taught since elementary school teachers carried rulers for chastising the less diligent learners among us.
    Gadget Gainer

  6. #26
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    From the book: Controls in Black and White Photography by Dr. Richard J. Henry. 2nd ed.,Focal press, 1986...

    "I want to digress a moment here to discuss the method of notating dilutions. Many authors in photography employ the form 1:2 when thy mean 1 part of the solution to be diluted added to 2 parts of the diluent, usually water. In most other scientific fields the notation 1:2 has an entirely different meaning, namely, "dilute 1 part of the solution to be diluted to a final dilution of 2 parts — thus, equal parts of each or 1+1. To avoid confusion, therefore, throughout this book I will use the notation 1+1, 1+2, 1+3, etc so that there cannot be any chance of confusion as to what is meant." — page 88.

    This book, now out of print (unfortunately), should be on the bookshelf of every serious black & white photographer. Henry used the Scientific Method to confirm or de-bunk some of the endless flood of words and opinions published over the years. Too bad he isn't around today to continue his investigative work.

    Reinhold

    www.classicBWphoto.com

  7. #27

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    Quote Originally Posted by gainer View Post
    Let's consider another proposition. In the face of so much buffering, will it really make a difference if you use ascorbic acid instead of sodium ascorbate? If not, then the TEA can be left out and a B solution of 1 gram of phenidone and 12 grams of ascorbic acid in glycol or glycerol used. As I review what I've been preaching, I see that 12 grams of ascorbic may not dissolve in 100 ml of glycol. If not, use 200 ml and double the dose to 20 ml/l of working A.
    Pat, the buffer seems pretty weak. There's potassium carbonate and then a small amount of the bicarbonate, of sodium sulfite and sodium metabisulfite. I'd worry about shifting the pH around using straight ascorbic acid.

    The formula looks interesting but I'd want to see noticeably better image qualities to deal with all these reagents (rather than mixing up PC-Glycol or something comparable).

  8. #28
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    Quote Originally Posted by Jordan View Post
    Pat, the buffer seems pretty weak. There's potassium carbonate and then a small amount of the bicarbonate, of sodium sulfite and sodium metabisulfite. I'd worry about shifting the pH around using straight ascorbic acid.

    The formula looks interesting but I'd want to see noticeably better image qualities to deal with all these reagents (rather than mixing up PC-Glycol or something comparable).
    Jordan, it should be easy enough to check. There would only be 1.2 grams of ascorbic acid in a liter of working strength A solution. I agree that I would want noticeably better image qualities than PC-TEA or PC-Glycol before I would go to the trouble of all that measuring and mixing. It is so easy to doctor up the working solution of either one with some sulfite or carbonate or whatever. That is what struck me first about FX55, and why I made some joking remarks.
    Gadget Gainer

  9. #29
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    Quote Originally Posted by Reinhold View Post
    From the book: Controls in Black and White Photography by Dr. Richard J. Henry. 2nd ed.,Focal press, 1986...

    "I want to digress a moment here to discuss the method of notating dilutions. Many authors in photography employ the form 1:2 when thy mean 1 part of the solution to be diluted added to 2 parts of the diluent, usually water. In most other scientific fields the notation 1:2 has an entirely different meaning, namely, "dilute 1 part of the solution to be diluted to a final dilution of 2 parts — thus, equal parts of each or 1+1. To avoid confusion, therefore, throughout this book I will use the notation 1+1, 1+2, 1+3, etc so that there cannot be any chance of confusion as to what is meant." — page 88.

    This book, now out of print (unfortunately), should be on the bookshelf of every serious black & white photographer. Henry used the Scientific Method to confirm or de-bunk some of the endless flood of words and opinions published over the years. Too bad he isn't around today to continue his investigative work.

    Reinhold

    www.classicBWphoto.com
    Thus, 1:1 really should mean 1 part mixed with 1 part to produce 1 part? In mathematical logic, IIRC, the colon indicates a ratio, not a sum. Alone, it does not specify the final quantity, but only the ratio between its parts.
    Gadget Gainer

  10. #30
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    Quote Originally Posted by gainer View Post
    Thus, 1:1 really should mean 1 part mixed with 1 part to produce 1 part? In mathematical logic, IIRC, the colon indicates a ratio, not a sum. Alone, it does not specify the final quantity, but only the ratio between its parts.
    Have to agree with Reinhold the 1:2, 1:3 etc system used to have a different meaning but increasing Americanisation/Globalisation has changed how we use these figure because Books of Fornulae etc are now aimed at Global markets..

    When I first started in photography it was more normal to use 1+1, 1+9 etc but when you saw 1:10 dilution that meant one part chemical was diluted to 10 parts, just occasionally the 1+9 would be in Brackets. 1:1 wasn't used as this was F.S. - Full Strength.

    In scientific terms diluting 1:10 or 1:100 means making a 10% or 1% solultion.

    However looking at older Agfa (Ansco), Kodak & Ilford Formulae books they all spelled out the dilutions, ie 1 part developer plus 9 parts water. Modern Ilford technical data sheets always use the + symbol, while Kodak however use the : to mean the same.

    Luckily we have come to accept that modern usage of 1+9 and 1:9 means the same thing.

    Ian

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