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  1. #41

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    Eric,

    Yes, H202 is hydrogen peroxide as I found out. Where did you say it should go into? Thanks!

  2. #42
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    Quote Originally Posted by eggshell
    Eric,

    Thanks again. That explaination is a little too quick for my sticky brain. What is H202? Do you mean to add 3% H202 to the mixed solution before pouring onto the paper for brushing?

    As I mentioned yesterday, the masked area left me with a colourless watermark-like stain. Again, the stain appears today even with newly mixed Sol. 2. So I did a test by applying a drop of Ferric Oxalate No 1 and a drop of No 2 on separate piece of paper. Developed & clear as I usually would. NO STAIN! My PO should be okay. My brush is thoroughly wash with HCA. Can't be that my coating area is too bright. The only thing I can think of that could go wrong is my palladium sol.3. I remember in earlier thread that Jorge had the same fog problem before and couldn't nail down where the fault was. Is my Palladium Sol.3 messed-up?

    Appreciate your kind response.
    H2O2 is hydrogen peroxide. One can use it as a contrast agent. I use 35% hydrogen peroxide when I make ferric oxalate from Ammonium Ferrous Sulfate. It can be added to the developer as well but I find that method of contrast control, hard to predict and replenish. And since there are other methods that are very predictable, why bother. But the adding of drops to a coating solution does work and is quite predictable. It is very cheap compared to the new wave of contrast control, sodium platinum which cost as much as normal platinum for printing.

    As far as your Palladium solution being messed up? Did you mix it to my mistyped (sorry again) answer? 5 salt to 3.5 PD? If so, you can always add the correct amount of PD to adjust for the mistake. If however, you used the proportions that are correct, 5g PD with 3.5 NaCl, then there is nothing to fix. Your speed gain was with which mix? to make 40ml or 55ml.

    The process of mixing chemicals for PT/PD printing is best looked at as a balancing act. We need FO combined with PD/PT solution and light to form an image. The amounts of each component can /should be optimized for each user as the big variable is FO. IF you haven't tried a little change in the drop counts, FO, PT, and PD along with your contrast agent (there are several) to see what works best for you, I recommend it.

    Eric

  3. #43
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    Add it to the FO and PD/PT coating solution. It can be diluted into 1.5 %, .75 % as with other contrast agents, size doesn't always work. It can keep for a few days, but when I used that method found that a fresh solution mix was wise, especially on very small adjustments on 5x7 prints. It has a big draw back as a system at needs for large amounts of contrast gain.

    Eric

  4. #44

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    Quote Originally Posted by EricNeilsen

    As far as your Palladium solution being messed up? Did you mix it to my mistyped (sorry again) answer? 5 salt to 3.5 PD? If so, you can always add the correct amount of PD to adjust for the mistake. If however, you used the proportions that are correct, 5g PD with 3.5 NaCl, then there is nothing to fix. Your speed gain was with which mix? to make 40ml or 55ml.

    Eric
    Eric,

    My mix is 5g PD with 3.5 NaCl. So nothing to fix as long as there is nothing wrong with the Maldon Sea Salt that was used. I mixed it to 55ml.

    As with the use of H202, is it used in addition to FO Sol. 2 or as a replacement for it.

    Thanks!

  5. #45
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    Quote Originally Posted by eggshell
    Eric,

    My mix is 5g PD with 3.5 NaCl. So nothing to fix as long as there is nothing wrong with the Maldon Sea Salt that was used. I mixed it to 55ml.

    As with the use of H202, is it used in addition to FO Sol. 2 or as a replacement for it.

    Thanks!
    AS a replacement or in addition. FO 2 (again a B&S thing, adopted by Arentz) is FO with added Potassium Chlorate. There is some discussion that you can have about balancing the Potassium Chlorate for use with PT or with PD or combinations. It is a contrast agent that WILL increase grain in your prints quickly with some papers, and notably when compared to peroxide, chromate, of Na2 (which can be substituted with Platinic Acid).

    Some users of the Chlorate method will prepare a separate bottle of Chlorate solution and add it. If you are making your negatives with reasonable care, you should be using little FO 2 (or B in many formula). In which case your FO that is suspending it WILL go bad before you use it up. You should also notice that there is a slight smell of chlorine in the air when you open the bottle of FO containing the chlorate. It has released some of the chlorine as gas;weakening your solution and its contrast ability. When I worked in a studio that used this method I cut the amount of Chlorate added to the FO by half as that suggested in the literature. Why? Two fold. It allows from greater control over increases in contrast and it forces you to use it up faster keeping it fresher and more consistent.

    This was a studio that would use liters of solution over a month or so. I routinely used burets to measure coating solutions.

    As for your salt, I don't know what is in your sea salt. Is there a portion that is Potassium Chloride? Non caking ingredients? I mix with purchased a ammonium chloride, sodium chloride. Why? certainty. The choice of the ions running around will affect color of your print and the different weights of K, NH4, NA or enough to make a small change. You printing will improve when yo eliminate variables. You can always reintroduce them later when you have a improved ability to point to a source of change rather than random chance.

    Eric

  6. #46
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    Hi Eric,

    Let me throw a question here.

    Why would anyone want to change the concentration of Pd solution from 15% to anything higher (yours is about 21%)? What kind effects does it have on different aspects of printing, i.e. speed, tone, contrast, etc? I would like to know about those before I try it.

    Thank you for your input.

    Warmly,
    Tsuyoshi



    Quote Originally Posted by EricNeilsen
    Don, The gram ratio of NaCl to PdCl2 is 5g/3.5g, but the mole ratio is 2:1. The amount of water added will change the molar concentration of the solution. I mix mine to make 40ml. I belive that B&S list that same amount to make 55ml. At the concentration I mix it is a .7M solution , B&S is lower. Since there was some question as to the purity of the salt one might get from the store such as Mortons, for example where there may be some weight that is NOT NaCl, an error on the side of slightly more weight is GOOD. THat assure you that you have enough NaCl to complete the complex solution.

    I haven't seen where a little NaCl will have serious adverse effect; just a lose of print speed.

    Eric
    ----- P R O J E C T B A S H O -----
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  7. #47
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    Quote Originally Posted by Shinnya
    Hi Eric,

    Let me throw a question here.

    Why would anyone want to change the concentration of Pd solution from 15% to anything higher (yours is about 21%)? What kind effects does it have on different aspects of printing, i.e. speed, tone, contrast, etc? I would like to know about those before I try it.

    Thank you for your input.

    Warmly,
    Tsuyoshi
    Tsuyoshi, My platinum printing experience started back in 1982. At that time the only reference that I had was a booklet from Tom Millea and phone conversations with Dick Sullivan at B&S. As the years went along, I had longed for a more complete source to fill in the gaps between my years in chemistry doing equations and what I was doing with PT/PD printing. Back in 1991 or 92, John Stevenson of the Platinum Gallery in Santa Fe, stopped by the Henningsen studio where I was assiting. (since 1982) with a paper from Mike Ware. WHile the paper was studying the printing with AFO, I could still see many similarities. In Mike's writings, he was using a .7 M Ammonium based Platinum and a .7M based Ammonium Palladium solution.

    The reaction that takes place with light requires that we have twice the amount of AFO or FO to match our metal salt. So a solution of 1.4M AFO is used. The FO compound has been describe as ill defined and there are many different slight variations to it. Stay with the most common, I mix mine to about 28% to 30% to get a 1.4M solution. The molar concentration of Standard potassium based platinum salt is .457M and that is at saturation. The saturation point of palladium chloride is much higher. If you are trying to balance the equation so that you have twice as much FO or AFO as metal salts, you shold look at molar solutions and NOT percent solution.

    The .7M palladium solution that I use is match with an equally strong solution of FO.

    You can use additional amounts of FO in your coating solution to increase contrast and speed. This is not the first place to start, or at least it is not the first place I'd start.

    If you mix up a batch and you find no benefit, you can always add water to adjust back to your more dilute standard solution of palladium. Remember it is the amounts of PdCl2 and NaCl that are in the 5/3.5 g ratio that is important.

    I had heard of many printers double coating and was also looking for a way to accomplish the same thing without brushing the paper twice.


    It works for me.

    Eric

  8. #48
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    Eric,

    Thank you for your explanation. My friend with a background of chemistry just explained to me what Molar is and how to calculate based on atomic weight.

    I understand that it is optimal to use .7M solution of Pd and mix with 1.4M solution of FO for pure Pd printing. What do you do if you start adding Pt to Pd and changing the ratio? Do you literarily have different M solution for Pd, provided that M solution for Pt is relatively lower at its saturation?

    Also, it occurred to me that is this a part the reasons why pure Pt print is unpredictable? It is about 3 times more at the point.

    Thanks again.

    Warmly,
    Tsuyoshi
    ----- P R O J E C T B A S H O -----
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  9. #49
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    Quote Originally Posted by Shinnya
    Eric,

    Thank you for your explanation. My friend with a background of chemistry just explained to me what Molar is and how to calculate based on atomic weight.

    I understand that it is optimal to use .7M solution of Pd and mix with 1.4M solution of FO for pure Pd printing. What do you do if you start adding Pt to Pd and changing the ratio? Do you literarily have different M solution for Pd, provided that M solution for Pt is relatively lower at its saturation?

    Also, it occurred to me that is this a part the reasons why pure Pt print is unpredictable? It is about 3 times more at the point.

    Thanks again.

    Warmly,
    Tsuyoshi
    I try and buy the amonium based platinum. I was able to get it from Engelhard but since it is not a normally stock item they have not had it in a while. I did recently get a supplier from Pradip Malde, the co worker with Mike Ware; An Investigation in Platinum and Palladium Printing, 1986. I highly recommend that you read it if give the chance.

    WHy does one use PT in print making? Color, Contrast? Well, I use it for those two reasons and since a contrast gaon is to be expected if extra FO is included, I don't sweat it. If I am using ammonium based platinum it is balanced because it can be mixed to achieve the .7M solution. And guess what? the prints have even more contrast and speed. I shared prints made with that type of platinum with Dick Suillivan back in 1993 or so. His response? He said that it would be bad for the industry to let people know. ???? He didn't want to sell it since he doesn't make it and there goes his profit margin. The down side? Yes, there is a down side. The potassium based platinum will sit happily in a bottle for years and years. The ammonium based will not. One should plan on using it within 6 months or so.

    You SHOULD NOT use H2O2 with it either as H2O2 is one way to pull platinum out of solutions.


    I have not had problems with pue PT prints being unpredictable. What do you mean? Perhaps, it is more unforgiving to mistakes in process control. It also requires dry conditions (faster at low RH), where PD likes humid (faster at high RH) conditions.

    The fact that potassium based platinum is at its saturation state when we use it, is a reason to keep it warm to assure that it stays that way.

    Eric

  10. #50

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    Quote Originally Posted by EricNeilsen

    As for your salt, I don't know what is in your sea salt. Is there a portion that is Potassium Chloride? Non caking ingredients? I mix with purchased a ammonium chloride, sodium chloride. Why? certainty. The choice of the ions running around will affect color of your print and the different weights of K, NH4, NA or enough to make a small change. You printing will improve when yo eliminate variables. You can always reintroduce them later when you have a improved ability to point to a source of change rather than random chance.

    Eric
    Eric,

    Here's what the label says: Maldon Sea Salt is a completely natural product without artificial additives, retaining valuable sea water trace-elements, such as magnesium and calcium.

    Sodium Chloride 98.80%,
    Potassium Chloride 0.018%
    Magnesium Sulphate 0.10%
    Calcium Sulphate 0.55%
    Moisture0.80%
    Insoluble Residue0.035%

    Do you suppose there is anything wrong with Potassium Chloride 0.018%?

    Thanks.

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