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  1. #11

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    Mr Crawley supplies two photos with the article. One is simply sea and waves, the other is tree bark. Both of which are difficult to capture unless the developer does a good job and it seems to. I can only assume that Mr Crawley has run a lot of films through the developer as he quotes times for a long list of films, including some no longer produced but which enthusiasts have probably stored.

    Provided you are willing to do your own mixing, keep a small range of chemicals on hand and have scales accurate enough to measure down to 0.1g, it seems to offer cheapness with indefinite keeping.

    It's just such articles that I'd like to see in B&W mag but all credit to AP and Mr Crawley for publishing it without any copyright. I couldn't see any drawbacks.

    pentaxuser

  2. #12

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    Quote Originally Posted by Ian Grant View Post
    There's something wrong with this no-one (normally) publishes a formula where developing agents are added just before use as solids.

    Ian
    Well, there is one precedent: Ryuji Suzuki's developers that contain Dimezone-S can be made with ordinary Phenidone but he recommended that the Phenidone be added as powder at the last minute because of its tendency to not keep well (according to his web site).

    My guess is that it's a very good developer (FX-55) but no manufacturer could deal with the issue of "just add this bit of powder before use."

  3. #13
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    Sometimes I wonder about Crawley. I've known enough Englishmen to know that some are not far from the Irish in enjoyment of a practical joke. He could make a very fine developer out of a large number of ingredients and have a large number of photographers believing that each one was absolutely indispensable. I think some Englishmen have gone so far as to hire Irish for their Gift of Gab to handle advertizing. How else can we get such lyrical descriptions of grain, acuity, edge effects, etc.? I speak from experience. My father was a singer with a Doctorate of Philosophy and Philology of English from St. Louis University, a choral director and the father of a girl and 4 boys by a beautiful woman from Poland. He did other things as well. His ancestors came from Ireland before the Revolution.
    Gadget Gainer

  4. #14

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    I'm interested in the sulfite.Ryuji's DS-2 has 20g/L.From an old msds, FX-50 part A had 12-14% w/w.IIRC dilution was 1+1+8 giving 12-14g/L working solution.
    In FX-55 sulfite is not a preservative and its probably not involved in the development reaction.The only reason it is there seems to be to uncover latent image specks and increase film speed.If this is the case, Crawley uses about 2.5+1.2 g/L as sufficient for this purpose.

  5. #15
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    Has anyone measured the pH of the working solution yet?
    There's a carbonate/bicarbonate buffer and the sulfite/bisulfite added.
    Looks like a soft working phenidone developer. Too low for the ascorbate to do more than extend the life of the phenidone?

    Murray

  6. #16

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    [QUOTE=gainer;678791]Sometimes I wonder about Crawley. I've known enough Englishmen to know that some are not far from the Irish in enjoyment of a practical joke. He could make a very fine developer out of a large number of ingredients and have a large number of photographers believing that each one was absolutely indispensable.

    Which are the bits of this developer that he is joking about/ aren't necessary/ add nothing to its efficacy?

    For those of us who are absolute beginners in this with little or no chemical knowledge, it is a little disconcerting to see posts from those who know much more which appear to cast real but unspecified( to my untrained eye) doubts about its efficacy.

    Is he recommending additional non essential chemicals? Why and what would be his motive? He does mention Silverprint as a stockist of most ingredients but I hardly think that he's in league with Martin Reed for what would be a paltry sum of money.

    It could equally be that those, knowledgeable on matters of photographic developers, are simply being whimsical and are not in fact casting any real aspersions towards Mr G Crawley's knowledge or motives.

    It's just that my knowledge doesn't extend far enough to tell the difference. I am a bit like the school student who has just started physics and is unable to understand and appreciate the humour in a conversation about the origins of the universe between say Albert Einsten and Steven Hawkins.

    Any clarification at a relatively simple level on the real benefits/ drawbacks on FX55 would be appreciated

    Thanks

    pentaxuser

  7. #17
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    I alluded to the possibility of some excess when I suggested, in essence, that PC-TEA would make a good part B. PC-TEA + water, of course, can be used as a complete developer. While Mr. Crawley's A solution is buffered up one side and down the other, TEA (AKA triethanolamine) is a pretty good buffer on its own.

    I didn't mean to imply that FX55 had any drawbacks except, possibly, complexity. It's just that I have seen a number of his formulae and various descriptions of their results. I did compare Acutol and PC-TEA critically once upon a time and could see no significant difference in results. Unfortunately, I can no longer do that comparison. However, if you have the makings of FX55, you will have the makings of PC-TEA if you add the TEA, and it would be a simple matter to use the PC-TEA as part B of the FX55 just for a comparison. I would say 10 or 20 ml of the PC-TEA stock might double for the phenidone-ascorbate of FX55.
    Basically, I was just making fun of FX55, as I feel Crawley might do to PC-TEA...just for fun.
    Gadget Gainer

  8. #18

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    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?

  9. #19
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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?
    There is no B solution, you add the dry B chemicals to the A dilution..EC

  10. #20
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    Quote Originally Posted by eclarke View Post
    There is no B solution, you add the dry B chemicals to the A dilution..EC
    Or, you make a B solution of phenidone and ascorbic acid in just enough TEA to neutralize the ascorbic acid, thus making it an equivalent of sodium ascorbate when it hits the water of the A solution. If you do that literally, your B solution will be a paste, so add an amount of propylene glycol to make it a convenient volume such that a certain number of ml will contain the amount of phenidone and ascorbate that you want to add to the A solution. You may use glycerol from the druggist in place of the glycol. Now when B joins A, the ions of everything can merilly dance around developing your film.

    Should you undertake to do it this way, the molecular weight of TEA is 149.2 and that of ascorbic acid is 176. Use the 99% TEA. You can scale the proportions to the total amount of ascorbic acid you want in your B solution.
    Gadget Gainer

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