From Pixels to Platinum Print (A Visual Representation)

August 13, 2013

Following on from the previous post, I have always wanted to show in one picture a visual representation of the process of turning a digital image file into an actual platinum print. Below is a simplified illustration in 3 steps using the Piezography 2 Digital Negative System. (Click image for higher resolution version)


Skógafoss-Iceland 2013,Jon Cone, Platinum/Palladium Print on Japanese Paper

1-Shows the Original Digital File

2-Shows the Original Digital File with Platinum Correction Curve

3-Shows the Flatbed Scan of the Platinum Print

Calibrating a digital negative system to be completely linear can be time consuming and the correction curve applied is different for each paper one uses, as is getting from steps 2 to 3 considerable more complex than one image can represent and involves printing the digitally corrected image onto transparency film, then hand coating, exposing and developing the platinum print in the darkroom, then scanning the print and making any changes neccassary to the original file, however I will illustrate these techniques in upcoming posts.

11 Responses to “From Pixels to Platinum Print (A Visual Representation)”

  1. Catherine Says:

    David, I will be very interested in your future posts. I have been trying to print digital negatives with Jon’s PZDN system using the selenium inks and I think I came close to a pretty good negative However, I am not sure about applying a curve. Is the curve applied to the negative or to one of the Methodology 3 curves that Jon provides? There were some shadows I wanted to open up and I was not successful.

  2. Matt Ebbers Says:

    David once again, thank you for sharing your knowledge and work flow. I can attest to the complexity of this process. In attempting to refine my curve this past weekend I managed to make it worse. Something changed in my system, i just have to figure out what it was. Back to the old curve for now.


  3. David Chow Says:

    Hi Catherine, the curve is applied to the negative rather than the methodology 3 curves in qtr. As you can see it is relatively mild compared to curves used by other negative creation methods, and you should be able to be open up the shadows with no problem. Are you printing in platinum?

    • Catherine Says:

      I am printing in palladium. I did apply a curve to the negative with a layer mask and then applied curve number 6 when I printed the negative on the pictorico. But when I made a palladium print it was awful because it came out darker everywhere so I must be doing something wrong.

      • David Chow Says:

        By curve No 6 do you mean that you applied the 1.6 density qtr curve? I have found that the 1.8 qtr curve works better with platinum/palladium printing. Have you also checked that all the inks are installed in the correct positions? The method I am using is a revised technique devised by Jon Cone that should be released imminently; it allows you to print both positive and negative prints without having to purge the inks.

      • Catherine Says:

        When I said curve No. 6 I did mean the 1.6 density qtr curve. I have actually tried 1.8 too but thought there was too much contrast in the print. All the inks are in the right position. I am using a 2880 so I did not think I had to purge the inks (the carbon inkset was installed before). I have refilled the cartridges once already.

        I took a class with Jon earlier this summer on printing with Piezography inks and he mentioned what beautiful work you do.

        I noticed in the picture you posted above that you had points placed all along the line. I did not do that. Would that make a difference?
        I appreciate the time you are taking to answer my questions.

      • David Chow Says:

        Okay that’s good that you have the ink cartridges in the right positions…you do have to concentrate a bit when you are refilling them all! I assume the K7 system you are using is not able to print positive prints? The new system I am using is able to and it does help having this option as it does help in calibrating when creating negatives on transparency film.

        The image you mention shows the correction curve for use with the Japanese paper i use with the 1.8 qtr curve. It has 16 points that one can move in order to fine tune the correction curve. How are you deriving your own correction curve? Are you using the PDN curve calculator?

  4. Catherine Costolo Says:

    I have worked with PDN but found it very difficult. After a class with Mark Nelson I bought a used densitometer so that did help some but I never really did achieve a good curve for my Cot 320 paper. I also was having trouble getting a good dmax. I was using a homemade UV printer that someone made years ago and so I thought it might help to get a new one in case the lights were not strong enough. I bought the new one with more powerful lights and it also has a vacuum pump installed. Now my times are between 3 and 4 minutes. Is that too fast?

    I thought working with Jon’s curves might make the process easier but maybe not. :>)
    Do I still need to derive my own correction curve? I am not sure how to do that using PZDN. Are you working with both PDN and PZDN?

    I simply added a curve with a layer mask to my digital neg but I put only one point on the curve.
    That might not be the right way to go about things.

    I can only print negatives.

    • David Chow Says:

      Okay…Did Mark go through the curve calculator with you? You don’t need to use the PDN system, rather just the curve calculator part of his workflow. Do you have the documentation that came with PDN.. it has a section that discusses curve creation.

      You will need to create a correction curve for your current PZ system however it should be no way near as extreme as those used with other negative creation systems, this will open up the shadow areas that you are having trouble with.

      In relation to not getting a good dmax from Cot320, this particular paper has never been the best for achieving a really high dmax however it can yield a nice print if the paper is from a good batch. My understanding is that Cot 320 is made by Arches and is essentially Platine with a light gelatin layer to aid coating. As Platine has not been as reliable for a while now it stands to reason that recent batches of Cot320 will also experience similar problems to Platine which has been poor dmax & grainy results. Did you purchase the paper recently? You might want to experiment with other papers if you are not getting a good dmax. I shall be testing version 3 of Revere Platinum once my samples arrive from Italy, the paper is made by Legion and has been getting positive reviews of late and shall be released soon.

      • Catherine Costolo Says:

        I have worked with the curve calculator. Right now I am in Italy for the next two months so when I get home in October I will begin again and will try some different paper. Do you have a suggestion for a paper to use?
        I also have some Platine but was not getting very good results.
        I will look forward to your review of the Revere Platinum.

        Thanks so much for the conversation. I have learned so much.

  5. Bishop Says:

    David — I have been reading your posts on digital negatives with great interest and am most intersted in your future posts and. I have not tried to print digital negatives with Jon’s PZDN system or even used the inks previously. I have requested prints to review the various inks and their output. If you have time will you provide further details on the curve creation steps? I believe this is the step which is most impacting my current efforts. I appreciate all the information you have provided to date…it has all been most helpful.

    Best regards — Bishop

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