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  1. #41

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    Quote Originally Posted by jdef
    Jorge,

    I know you don't like to waste a lot of time testing developers, and I don't blame you, but in case you're interested, I thought I'd mention my Rapid Universal developer for your negs, as it produces virtually no fog. It is not a staining developer like Pyrocat, so general stain is not an issue. I've recommended it to another Platinum printer who wanted to try it, but I don't know if he ever did. DRU can be used several ways, including as a divided developer. I won't waste a lot of space here describing the many ways it can be used, but suffice it to say that DRU will develop TMY to the contrast required for platinum printing without fogging. If you're interested, PM me, and I'll give you the formula and more details.

    Rotary processing, tray processing and edge effects

    Although I don't use Pyrocat HD, except for testing, I do use Hypercat, which is a catechol/ascorbic acid developer, which shares some characteristics with Pyrocat HD. In my experience, it's much easier to increase sharpness with these developers, than to reduce it. In other words, no matther how you process your film in these developers, it's going to be very sharp, and using semi-stand development to enhance edge effects could easily lead to harsh prints, especially for portraits. I was surprised to see recommendations for semi-stand development for portrait negs above. Most of my work is porraiture, for which I use continuous agitation for the smooth, creamy midtones I love. I have no problem getting enough sharpness, even with continuous agitation, and I'm assured of perfectly even development, with much shorter development times, and all of the benefits that brings. A friend has lent me a scanner, and I'm going to try to attach a scan of a print made from a HP5+ neg developed in Hypercat 1:1:100 for 6min./70F with continuous agitation. Please excuse any scanner-user defects.

    Jay
    Is this an ascorbic acid developer? I was not very happy with Xtol and decided to stick with Pyrocat, but if you have something better I might give it a try. I am looking for a developer capable of doing G bars from 0.28 to 0.9. If your developer can do this without an actinic stain post the formula and I will give it a shot.

  2. #42

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    Quote Originally Posted by jdef
    Hi Jorge.

    DRU

    water 750ml

    Sodium sulfite 36g

    Hydroquinone 3.6g

    Sodium carbonate 20g

    Borax 10g

    Phenidone .5g

    Sodium ascorbate 4.5g

    BZT 1% 10ml

    water to 1 liter


    To make a working solution for rotary processing, dilute 1:5 for times in the 5 minute range, or 1:10 for times in the 10 min. range, etc., up to 1:20.

    You might be interested in using this developer as a two-bath, for very economical/repeatable tray use. To use as a two-bath, simply leave the carbonate and borax out of the A solution, and make up a 10% sodium metaborate bath for the B solution, or for a softer working developer, you can try a 1% borax bath for the B bath. For the metaborate version, try 3min A/ 2min B. Contrast can be controlled over a wide range by varying the time in the A solution. Normal, continuous agitation in the tray is fine for the A bath, but for the B bath, lift one corner of the tray every 15 seconds.

    If you have any questions or suggestions, feel free to contact me directly. If you decide to try this, I hope you'll let me know how it works out.

    Jay
    Thanks for the quick reply but I think you screwed the pooch with all them ingredients I dont have. I would have to buy Borax, BZT, Hydroquinone and sodium ascrobate. While this is easy for you in the US, it is a PITA for me with all the import and shipping charges.

    Sorry, maybe next time.

  3. #43

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    Quote Originally Posted by jdef
    Jorge,

    if you'd like, I could send you the ingredients, pre-measured. Just add water.

    Jay
    Hey men, if you want to do that I will gladly waste a few negatives testing the developer and making a few prints. If you got the plotter program I can also send you my results to compare with yours.

  4. #44

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    Quote Originally Posted by jdef
    Hi Jorge.

    I don't have any of the BTZS software (wish I did), so I do everything manually. I know. I've always thought this would be a promising developer for alt printers. due to its ability to build contrast without fogging, but I don't do enough alt. printing myself to really verify that. Tomorrow, I'll send a kit for one liter of DRU, and another for a liter ea. of A&B solutions for the divided version. That should be enough for you to give it a try, and if you like it, I can get you more.

    Jay
    Thanks, I will love to try it. What I will do is I will test it, make a few prints and then send you a print and I will print the curves from the program as well as the charts, they might be of some help to you in the future.

  5. #45

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    Quote Originally Posted by Jorge
    I am almost sure it (high fog levels) is due to aerial oxidation.
    Jorge - have you thought about using a nitrogen tank to blanket the developer in the Jobo drum with a nitrogen?

    I've started doing that with PMK and not only does it reduce the base+fog level, but with PMK I find it reduces development time by about 30% from my previous technique (using 1500 ml in the 3010 drum).

    Kirk - www.keyesphoto.com

  6. #46

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    Quote Originally Posted by Kirk Keyes
    Jorge - have you thought about using a nitrogen tank to blanket the developer in the Jobo drum with a nitrogen?

    I've started doing that with PMK and not only does it reduce the base+fog level, but with PMK I find it reduces development time by about 30% from my previous technique (using 1500 ml in the 3010 drum).

    Kirk - www.keyesphoto.com
    Kirk,

    I have read your description of how to do this, and frankly it sounds much more complicated than other viable alternatives that one might consider for reducing general stain from excessive oxidation. One could, for example, modify the PMK by adding some sulfite or ascorbic acid, which would also make PMK more energetic and reduce development times, or you could just change developers.

    What am I missing. Why so much trouble just to use PMK as is? Why not just modify PMK (and the fixes have been know for years), or use a more suitable developer for rotary processing?

    Sandy
    Last edited by sanking; 08-24-2005 at 08:09 AM. Click to view previous post history.

  7. #47

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    Quote Originally Posted by sanking
    What am I missing. Why so much trouble just to use PMK as is? Why not just modify PMK (and the fixes have been know for years), or use a more suitable developer for rotary processing?
    Sandy - good question. To start with - for me, I like the convenience of the Jobo processor. I never could do may sheets at a time with tray processing without getting scratches and I went to a Jobo many years ago instead of trying to teach myself tray processing (and perhaps wasting a lot of film in the process). I like that I never have scratches with the Jobo and the uniformity of processing and the abitliy to process in the daylight and even walk away from the machine durings runs are valuable to me.

    And actually, I was happy with my results with PMK for silver printing by using 1500 mls in an Expert drum - I really had no reason to pursue any modification to the PMK. So it was not something that I did to try and solve some problem I was having, just something I tried and found worked really well.

    What happened was I noticed my dad had a 80 cu ft nitrogen tank sitting around his shop unused, and for another $40 more, I got a regulator. A few more bucks for some 1/8th in tygon tubing and a few gas fittings, and I had a nitrogen bath system. So I just gave it a try. It only takes a liter per minute of gas flow, and it only runs for the prewash and devleoper time, to it is not on that long. And it appears that the tank will last a very long time with this kind of use. So the investment of a tank would not be much in the long run. Especially considering the investment in the Jobo in the first place.

    As far as mods to the PMK formualtion go - I looked in the Book of Pyro, and it seemed that Gordon seemed to like the nitrogen approach best, so I figured I'd give it a try when the opportunity arose.

    It's really simple to use as well. I just thread the Tygon tube down the throat of the Jobo lift - that takes less than 30 seconds. The I put the drum on, and I simply open the main valve on the nitrogen tank. I've already got the flow set. So that's it - less than a minute of time.

    I haven't tried it with Pyrocat yet - I've only run one batch of it through the Jobo so far, but I'm sure it would eliminated any aerial oxidation issues that would arrise from it's use in a Jobo. Hence my suggestion.

    As for mods to PMK, off hand, I can think of adding sulfite/bisulfite to it - and I think that diminishes some of the stain, right? - so I wanted to avoid that. And for Rollo Pyro, I've never tried it. I guess I have an hangup about developers that use 3 developing agents when 2 should do... And does it produce as much stain as PMK?

    Kirk

  8. #48

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    Quote Originally Posted by Kirk Keyes
    As far as mods to the PMK formualtion go - I looked in the Book of Pyro, and it seemed that Gordon seemed to like the nitrogen approach best, so I figured I'd give it a try when the opportunity arose.

    As for mods to PMK, off hand, I can think of adding sulfite/bisulfite to it - and I think that diminishes some of the stain, right? - so I wanted to avoid that. And for Rollo Pyro, I've never tried it. I guess I have an hangup about developers that use 3 developing agents when 2 should do... And does it produce as much stain as PMK?

    Kirk
    I think Gordon Hutchings recommended a nitrogen burst system of development as the method of agitation, with the solution remaining still for the rest of the time. Personally I think this would be a wonderful method of development but for various reasons have never gotten around to building such a system. But as best I understand this, his use is very different from what you are doing with rotary processing.

    Adding extra sulfite to PMK, in the right amount, will not diminish stain. It will simply reduce the level of stain with rotary processing back toi the level you get with tray processing. Adding extra will also increase energy. If you add too much, however, you will reduce Stain. Anchell and Troop in The Film Developing Cookbook suggest adding about a pinch (0.3 g/L) of sodium sulfite to each liter of working solution. This will not work with Pyrocat-HD, however, as any extra sulfite kills the stain, though it makes the developer much more energetic.

    I share your views about three developing agents. Two tango very well, with three you get some real nasty dancing and never know what the next move might be.

    Anyway, I though what you did was pretty ingenious, but if the purpose was to reduce general stain from oxidation there appear to be easier solutions.

    Regarding Rollo Pyro, yes, it stains a lot, in fact every bit as well as PMK. I don't think it is quite as sharp as PMK, however, though for most work who could tell the difference?

    Sandy

  9. #49

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    Quote Originally Posted by sanking
    I share your views about three developing agents. Two tango very well, with three you get some real nasty dancing and never know what the next move might be.
    Yes - that's for sure!

    Quote Originally Posted by sanking
    Anyway, I though what you did was pretty ingenious, but if the purpose was to reduce general stain from oxidation there appear to be easier solutions.
    Thanks for the ingenious comment. I'ts been a while since I looked in the BoP for I may have forgotten my reasoning... Or perhaps it was my chemistry background and it seemed a natural solution to aerial oxidation. As I said, stain was not really my concern. And the decrease in development times was welcome, about 30% shorter than by previous technique.

    By the way - did you know that a strong solution of pyrogallol in a strong solution of potassium hydroxide has been used to scrub/remove oxygen from air by bubbling the air through it?

  10. #50

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    Quote Originally Posted by jdef
    Isn't a development byproduct of MQ or PQ developers a developing agent as well? Wouldn't that make any MQ or PQ developer a three-agent developer?
    Jay - interesting point. Your question hints at the reasons that simpler formulations are easier to design. Optimizing 2 componants will hopefully be easier than optimizing 3.

    Think about something like Rollo Pyro with Pyrogallol, metol, and ascorbic acid. So does that one turn into a 5 or 6 reducing agent developer once the byproducts start to build up?

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