Palladium/Platinum contrasting with B&S FO - chlorate

Discussion in 'Alternative Processes' started by scootermm, Dec 21, 2005.

  1. scootermm

    scootermm Subscriber

    Messages:
    1,865
    Joined:
    Jun 10, 2004
    Location:
    Austin, TX
    Shooter:
    ULarge Format
    Palladium/Platinum NA2 explanation (formerly B&S Chlorate thread)

    So Ive heard on many fronts that using NA2 for a contrasting agent is a much better method than the Chlorate added to Ferric Oxalate in their solution #2. I am working on a series of prints and have been using the Solution #2 for contrast control and it is actually doing a pretty good job. Its rare that I use alot of the #2 solution but this one I really found it helped the negative and resulting print.

    Thought I would share the results with anyone whos in a similiar place as myself (still feeling their way through pt/pd printing)

    I still plan on trying the NA2 as contrast control in the future but have been getting fairly good results with the basic setup that comes with the B&S kit. (of course Ive long since gone through a starter kit :smile: )

    heres the test strips I came up with..
     

    Attached Files:

    Last edited by a moderator: Dec 22, 2005
  2. Kerik

    Kerik Member

    Messages:
    1,467
    Joined:
    Nov 24, 2002
    Location:
    California
    Shooter:
    Medium Format
    You might want to try this test on an image that has a lot of smooth, even toned areas. I think you'll see grain and lose the creamy quality of pt/pd. An image like you've shown is all texture and graininess is much less apparent. These look pretty good, though.
     
  3. scootermm

    scootermm Subscriber

    Messages:
    1,865
    Joined:
    Jun 10, 2004
    Location:
    Austin, TX
    Shooter:
    ULarge Format
    kerik, Im looking forward to hopefully getting the NA2 chemicals in january and testing it out and comparing on some "sky" type images... you and many others have mentioned the same thing, which is tantamount to scripture (especially when I test it out for myself). Guess for right now Im just lucky this series is very textural and the possible graininess gets hidden by it.
     
  4. clay

    clay Subscriber

    Messages:
    1,124
    Joined:
    Nov 21, 2002
    Location:
    Asheville, N
    Shooter:
    Multi Format
    Any particular reason you are using more total metal solution drops than ferric oxalate drops in your drop count? I always use the same volume of each with the thought being that if there is no ferric to convert the metal, it just ends up being washed down the drain.
     
  5. scootermm

    scootermm Subscriber

    Messages:
    1,865
    Joined:
    Jun 10, 2004
    Location:
    Austin, TX
    Shooter:
    ULarge Format
    no excuse other than misinformed. The drop count tables Ive seen always had like one or two drops (depending on the print size) less total FO than metal. dually noted and thanks for the info clay, me showing my ignorance and newbieness
    :smile:
    edit note: the JPG should read 9 drops of PD and 3 drops of PT I misslabelled the file.
    still one drop more than needed so I think Ill start adjusting that to save some solution.
     
  6. Thomassauerwein

    Thomassauerwein Member

    Messages:
    1,627
    Joined:
    Apr 20, 2003
    Location:
    Southern Cal
    Shooter:
    Large Format
    NA2 is great! you don't need much and there is adjustment in exposure but it is very conveniant and less grain. I only use about on average 1/2 a drop.
     
  7. photomc

    photomc Member

    Messages:
    3,575
    Joined:
    Jul 20, 2003
    Location:
    Texas
    Shooter:
    Multi Format
    OK, Matt...even more newbiee to the DOP process, what is NA2? I keep hearing about it, but have not seen anything on the B&S site. Guess I need to pick up Dick Arentz book, I have the Chris James book (which I find good for coverage of all the differetnt alt. process), and was considering the Sullivan & Weese book, in place of Arentz book. Plan to give DOP Pld a try after all of the POP (Zia's) to compare.
     
  8. Ray Bidegain

    Ray Bidegain Member

    Messages:
    90
    Joined:
    Oct 22, 2003
    Location:
    Portland, Or
    Shooter:
    8x10 Format
    Matt:

    I have been using the Na2 for a while now and the level of contrast increase is much higher than the #2 FO. The one thing I do miss however is the ability to add in more platinum to the mix with out increasing the contrast. All the prints basically become palladium with very small amounts of platinum. Before with he #2 FO I was able to make changes to the look of the prints by changing the PT to PD ratio. Does anyone know if you can still add straight Platinum#3 into the mix when using Na2 for contrast control?


    Ray Bidegain
     
  9. Peter Schrager

    Peter Schrager Subscriber

    Messages:
    2,046
    Joined:
    Jul 19, 2004
    Location:
    fairfield co
    Shooter:
    Large Format
    Pall #3

    Yes Ray-you can add one drop to the mixfor incresed black...
    Best, Peter
     
  10. Joe Lipka

    Joe Lipka Member

    Messages:
    809
    Joined:
    Sep 24, 2002
    Location:
    Cary, North
    Shooter:
    4x5 Format
    Na2 is what we call Sodium Chloroplatinate. I use it because FO #2 is evil (Jorge says so and I don't argue with Jorge on this topic :D ) and was the cause of most of my failures in Pt/Pd printing. Even though it does contain platinum, I don't subtract that amount from the Pt contribution of my sensitizer.

    Would any of the tech wizards (or alchemists) out there be able to do a comparision between the Na2 and the Potassium Chloroplatinite's contribution of Platinum metal to the sensitizer formula?
     
  11. colrehogan

    colrehogan Member

    Messages:
    2,016
    Joined:
    May 11, 2004
    Location:
    St. Louis, M
    Shooter:
    Large Format Pan
    It's not so much the contribution of the Pt metal to the formula, but a matter of the Pt metal changing oxidation states in an oxidation/reduction reaction. The difference is the oxidation state of the Pt metal in each solution. In Na2PtCl6 (sodium chloroplatinate) the platinum has a 4+ oxidation state. vs. the K2PtCl4 (potassium chloroplatinite) in which the platinum has a 2+ oxidation state.
     
  12. Joe Lipka

    Joe Lipka Member

    Messages:
    809
    Joined:
    Sep 24, 2002
    Location:
    Cary, North
    Shooter:
    4x5 Format
    Can you translate that into English?
     
  13. Thomassauerwein

    Thomassauerwein Member

    Messages:
    1,627
    Joined:
    Apr 20, 2003
    Location:
    Southern Cal
    Shooter:
    Large Format
    Joe, the way I think of it is: NA2 tans darker values faster with a bit more contrast. Kind of like printing multiple contrast does in silver. At the exposure level rather than in the devloper. doing it at the developer level seems to push existing imformation within the emulsion further which seems to effect the grain. Kind of like push processing.
    I don't know all the teck talk stuff so this is an observation only.
     
  14. Sponsored Ad
  15. clay

    clay Subscriber

    Messages:
    1,124
    Joined:
    Nov 21, 2002
    Location:
    Asheville, N
    Shooter:
    Multi Format
    In simple terms, the Na2 consumes twice as much ferrous oxalate (ferric oxalate is converted to ferrous by UV light) than the palladium salt during the final reaction where ferrous converts back to ferric and causes the metals in the paper to reduce to the tiny particles that end up embedded in the fibers of the paper to form the image. Because it consumes the sensitizer at twice the 'normal' rate, it has a preferential effect in restraining the development of highlights, which have very little 'activated' sensitizer anyway. This causes the increase in contrast in the final image.

    By way of a simple example, say a highlight area has 4 molecules of 'activated' ferrous and a shadow has 128 molecules of the same. Two extra molecules of Na2 in each print area would totally consume the 4 molecules of ferrous in the highlights, leaving none to convert the remaining palladium. The same thing happens in the shadows, but the reduction is only taking 4 out of 128 molecules of ferrous out of commission, leaving the rest (128-4=124) to reduce the palladium to image forming particles. The net result is hardly any effect on the resulting print density in the shadow areas on a percentage basis, but a profound effect in the resultant print density of the highlight areas.

    This is vastly simplified, but that is basically how the contrast agents all work. The differences between the contrast agents come about in the side effects they create. The chlorates tend to cause the image-making particles to clump together and cause graining, while Na2 does not have this annoying tendency.

    That is probably way more than anyone cares to know about this stuff. The simple fact is that the Na2 is just a good contrast increasing agent without the bad side effects that come with using chlorate in the sensitizer.


     
  16. Kerik

    Kerik Member

    Messages:
    1,467
    Joined:
    Nov 24, 2002
    Location:
    California
    Shooter:
    Medium Format
    Awesome! That's the best explanation I've read on how Na2 works. (Below is an artist's rendition of Clay explaining this phenomenon.)
     

    Attached Files:

  17. clay

    clay Subscriber

    Messages:
    1,124
    Joined:
    Nov 21, 2002
    Location:
    Asheville, N
    Shooter:
    Multi Format
    You should see my new Christmas beanie. It plays Jingle Bells when the propeller turns.

     
  18. Michael Mutmansky

    Michael Mutmansky Member

    Messages:
    345
    Joined:
    Sep 7, 2002
    Location:
    Sacramento
    Shooter:
    ULarge Format
    Kerik,

    I know a person who wears double-breasted shirts with TWO pocket protectors. He calls it 'full frontal nerdity'.

    ---Michael
     
  19. colrehogan

    colrehogan Member

    Messages:
    2,016
    Joined:
    May 11, 2004
    Location:
    St. Louis, M
    Shooter:
    Large Format Pan
    I guess Clay and I don't speak English, we speak chemistry. :D
     
  20. scootermm

    scootermm Subscriber

    Messages:
    1,865
    Joined:
    Jun 10, 2004
    Location:
    Austin, TX
    Shooter:
    ULarge Format
    so Ive edited this thread title so its more fitting to the topic. Hopefully thatlly make it searchable. :smile: good explanation clay.
     
  21. Thomassauerwein

    Thomassauerwein Member

    Messages:
    1,627
    Joined:
    Apr 20, 2003
    Location:
    Southern Cal
    Shooter:
    Large Format
    It still needs a bit of dumbing down. Is It light reactive or chemical reactive? I only have one pocket and no protecters.
     
  22. clay

    clay Subscriber

    Messages:
    1,124
    Joined:
    Nov 21, 2002
    Location:
    Asheville, N
    Shooter:
    Multi Format
    Chemical reactive. The light sensitive compound is the ferric oxalate.The contrast agent just consumes (oxidizes) more of it during the image formation process.
     
  23. clay

    clay Subscriber

    Messages:
    1,124
    Joined:
    Nov 21, 2002
    Location:
    Asheville, N
    Shooter:
    Multi Format
    You can imagine my embarrassment when after ten years of marriage I realized my wife was not saying " Talk nerdy to me".

     
  24. Michael Mutmansky

    Michael Mutmansky Member

    Messages:
    345
    Joined:
    Sep 7, 2002
    Location:
    Sacramento
    Shooter:
    ULarge Format
    Let me go on the record as saying that I have never seen Clay wearing a pocket protector of any kind, let alone a pair of them. There was no implication that Clay is nerdy in my funny, but true, OT contribution to this thread.

    I do think he may have geeked out on us a little with that description, however.

    ***Please note that neither nerds nor geeks are protected under federal anti-descriminatory laws. I think that means it's open season.***
     
  25. sanking

    sanking Member

    Messages:
    4,813
    Joined:
    Mar 26, 2003
    Location:
    Greenville,
    Shooter:
    Large Format
    I hate to show my ignorance, but what is a pocket protector?

    Sandy


     
  26. scootermm

    scootermm Subscriber

    Messages:
    1,865
    Joined:
    Jun 10, 2004
    Location:
    Austin, TX
    Shooter:
    ULarge Format
    Here you go sandy...
    [​IMG]