Platinum prints from digital negatives

[Vaughn]

"Adding EDTA to the developer": I have never heard of that. EDTA is fairly safe (it is a food additive), but I would be interested on why it would be considered a hazard. You used Hypo Clearing Agent -- if you used Kodak's, I believe it has some in it. But just about any platinum printer will eventually come up with their own clearing routine. I use a citric acid first bath, followed by two baths of HCA (or Sodium sulfite) and EDTA.

From what I understand about digital negatives (which would not fill a thimble), one of their strong points is by standardizing one's coating mixture, paper and processing steps, you then only need to make changes in the digital negative to match what you see on your monitor...unless one wishes to change print color and/or paper. Then one would test and create a new profile (if that is the proper word) for printing the negative with the new paper, etc). Not really different than the way I work -- I attempt to expose and develop the negatives to print without any contrast agent in the coating solution or developer.

You can get rich prints with Ammonium citrate -- you would just have to test and change your printing profile to match the developer. But the color will be different than Potassium oxalate. Again, congrats on a great workshop and excellent prints!

[bob carnie]

Hi Vaughn

What is your Citric Acid mixture? - and do you add EDTA to your Hypo Clear and if so how much?.

I have made PT PD prints from In Camera negs, Enlarger Negs and now as well digital negs. I am using a single developer now but would like to gravitate to three, one with more and one with less contrast capabilities.

Using digital negatives I have found that its pretty fool proof , basically a bit of density correction to taste, but I do think three dev's would be quite nice to have . I doubt I would ever go back to enlarged negatives, and Ultra Large Format does not interest me. I am solarizing everything and making tonal separation negatives to suit my needs , trying to do this old school would cause me to lose all my hair , and there is not much left.


Basically by controlling your negatives with exposure and development you are indeed working to a Profile that you know is right for your work. I applaud this skill level as one needs to do quite a few thousand films IMHO to get to this point.

"Adding EDTA to the developer": I have never heard of that. EDTA is fairly safe (it is a food additive), but I would be interested on why it would be considered a hazard. You used Hypo Clearing Agent -- if you used Kodak's, I believe it has some in it. But just about any platinum printer will eventually come up with their own clearing routine. I use a citric acid first bath, followed by two baths of HCA (or Sodium sulfite) and EDTA.

From what I understand about digital negatives (which would not fill a thimble), one of their strong points is by standardizing one's coating mixture, paper and processing steps, you then only need to make changes in the digital negative to match what you see on your monitor...unless one wishes to change print color and/or paper. Then one would test and create a new profile (if that is the proper word) for printing the negative with the new paper, etc). Not really different than the way I work -- I attempt to expose and develop the negatives to print without any contrast agent in the coating solution or developer.

You can get rich prints with Ammonium citrate -- you would just have to test and change your printing profile to match the developer. But the color will be different than Potassium oxalate. Again, congrats on a great workshop and excellent prints!

[Vaughn]

Hi Vaughn

What is your Citric Acid mixture? - and do you add EDTA to your Hypo Clear and if so how much?.

I have made PT PD prints from In Camera negs, Enlarger Negs and now as well digital negs. I am using a single developer now but would like to gravitate to three, one with more and one with less contrast capabilities.

...

Basically by controlling your negatives with exposure and development you are indeed working to a Profile that you know is right for your work. I applaud this skill level as one needs to do quite a few thousand films IMHO to get to this point.

Citric acid 1st bath -- 3% (30 grams in 1000ml). I replace when too yellow with a fresh bath.

One to two tablespoons of EDTA to the HCA. If I do not have KHCA, I use one tablespoon each of EDTA and Sodium sulfite per liter. I once used the KHCA at 2x strength, and it started to bleach the prints -- turn them muddy-looking.

Negative control -- one has to be willing to keep good notes on SBR, film developing results and printing methods/results. And be willing to accept failures...even with once-in-a-lifetime images. I have made many many negatives -- no idea how many over 35yrs of LF work. But I cut my teeth on producing 4x5 negatives taken under the redwoods and printing in silver gelatin...not a 'normal' situation for most folks, then negatives for carbon printing (for my printing method, I need more contrast than DOP platinum printing can deal with).

I do have some wonderful carbon prints made from negatives that I gave too much development to for platinum/palladium printing. Does not always work, as the carbon printing reverses the image and the image may not work reversed.

Multiple developers -- some folks add a little Ammonium (or Potassium) dichromate to their pt/pd developers to boost contrast -- that might work well for you, Bob.

[Michael Mutmansky]

I am surprised that Potassium oxalate was the chosen developer for a 'safe' methodology. Ammonium citrate would have been a far superior developer in that situation. The process itself is neither safe or unsafe...that is more dependent on one's working methods. Silver gelatin printing is safe unless your methodology for some strange reason includes drinking the selenium toner or bathing in the Potassium cyanide. I have asthma now because I was using an unsafe method (blow-drier) of drying the pt/pd coated paper without any protection for my lungs (mask, etc). I now air dry with a fan for a safety and for a superior print.

The platinum and palladium solutions can be bought as liquid or as a powder. Very few workers make these from scratch. B&S sell it in both forms (the powder for is mostly for shipping overseas) and they make a very good product...very consistent and their Ferric oxalate has an excellent life-span.

Tween is optional...I have never used it in the 19 years I have been making pt/pd prints. But I might pick up some as I think it might be helpful for a new (for me) way of coating that I am working with.

Absolutely agree on the Am. Citrate as the safer developer... That is a head scratcher to me if you are trying to be absolutely safe. I use Pot. Oxalate, but it is always covered when it is not in the tray, where it sits only for the duration of the development. I also have a exhaust at the back of the sink to pull fumes away from me. Custom made by me to fit my sink.

I use citric acid and sodium sulfite and sometimes a little EDTA for the clearing baths. It seems to have the least amount of odor compared to a lot of other clearing baths that I have tried.

For heaven's sake everyone, don't use HCl for anything if you can help it. Talk about messing with your lungs. Way to volatile and aggressive on the cilia in the lungs.

[bob carnie]

Hi Vaughn

Thanks for that , its fun to know that some neg's can work for one process or another, we all screw up so if you learn a few processes you can look amazing. My solarization negatives are pretty much useless for any direct
process but when scanned and then punched up in PS they are magnificent for gum over pt pd.

If you don't mind could you give me a per litre % amount of Ammonium Dicromate to add to my developer?
I use KHCA so no need for EDTA?

Michael- HCI what is this? and in what context are you referring to regarding safety?

Bob

Citric acid 1st bath -- 3% (30 grams in 1000ml). I replace when too yellow with a fresh bath.

One to two tablespoons of EDTA to the HCA. If I do not have KHCA, I use one tablespoon each of EDTA and Sodium sulfite per liter. I once used the KHCA at 2x strength, and it started to bleach the prints -- turn them muddy-looking.

Negative control -- one has to be willing to keep good notes on SBR, film developing results and printing methods/results. And be willing to accept failures...even with once-in-a-lifetime images. I have made many many negatives -- no idea how many over 35yrs of LF work. But I cut my teeth on producing 4x5 negatives taken under the redwoods and printing in silver gelatin...not a 'normal' situation for most folks, then negatives for carbon printing (for my printing method, I need more contrast than DOP platinum printing can deal with).

I do have some wonderful carbon prints made from negatives that I gave too much development to for platinum/palladium printing. Does not always work, as the carbon printing reverses the image and the image may not work reversed.

Multiple developers -- some folks add a little Ammonium (or Potassium) dichromate to their pt/pd developers to boost contrast -- that might work well for you, Bob.

[Vaughn]

Sorry, Bob. Hopefully someone else can help you with the dichromate question as I have not used it and have not paid attention to amounts when I have seen it discussed.

I still add EDTA to KHCA, as the amount of EDTA native to KHCA is not great. (I add one tablespoon per liter). I have not tried decreasing the amount to see what would still work.

[bob carnie]

I have been in discussions with Ian Leake about this a while back, I started with a simple setup with tailor making the negatives via QTR but I am
wanting to be a little more open to multiple developers with exposure to control the final print a bit more. I will look into his recommondations.

thanks about the EDTA.

Sorry, Bob. Hopefully someone else can help you with the dichromate question as I have not used it and have not paid attention to amounts when I have seen it discussed.

I still add EDTA to KHCA, as the amount of EDTA native to KHCA is not great. (I add one tablespoon per liter). I have not tried decreasing the amount to see what would still work.

[sanking]

If you don't mind could you give me a per litre % amount of Ammonium Dicromate to add to my developer?
I use KHCA so no need for EDTA?

Bob

Bob,

Dick Arentz has a table contrast control with sodium dichromate on p. 70 of the second edition of his book, Platinum and Palladium Printing.

He mentions that the method can only be used with potassium oxalate developer, but I remember for sure that I used it with sodium citrate as the developer with ammonium dichromate and it worked fine.

Sandy

[Michael Lloyd]

"Adding EDTA to the developer": I have never heard of that. EDTA is fairly safe (it is a food additive), but I would be interested on why it would be considered a hazard. You used Hypo Clearing Agent -- if you used Kodak's, I believe it has some in it. But just about any platinum printer will eventually come up with their own clearing routine. I use a citric acid first bath, followed by two baths of HCA (or Sodium sulfite) and EDTA.

From what I understand about digital negatives (which would not fill a thimble), one of their strong points is by standardizing one's coating mixture, paper and processing steps, you then only need to make changes in the digital negative to match what you see on your monitor...unless one wishes to change print color and/or paper. Then one would test and create a new profile (if that is the proper word) for printing the negative with the new paper, etc). Not really different than the way I work -- I attempt to expose and develop the negatives to print without any contrast agent in the coating solution or developer.

You can get rich prints with Ammonium citrate -- you would just have to test and change your printing profile to match the developer. But the color will be different than Potassium oxalate. Again, congrats on a great workshop and excellent prints!

To be honest, I don't remember what the deal with EDTA was. It had something to do with mixing with something else. I just checked OverExposure (book) and HCA and EDTA mixed didn't come up as a problem. Muriatic acid, Patrick Alt's clearing agent of choice, has issues. Potassium Oxalate, when heated, gives off fumes but we didn't heat ours. Most people do and I probably will. Maybe outside? Idk

Your understanding of the dig neg strong points is correct. Spot on actually. Bob Carnie nailed it down even more.

Since I'm just starting out I'm interested in all of it. I haven't discounted Ammonium citrate. I don't have any, yet.

For me, as someone who basically missed the "darkroom age" (definitely not extinct though), I like the process of converting a digital file to a negative, then watching it come alive on paper that I coated, in a tray of chemicals that I mixed, and then seeing and touching the print after it's dried. Basically I take a very ordered and precise piece of binary data, use light (wave or particle?) to transfer it to a very random and disordered piece of paper that's been randomly slathered with bits of metal and chemical, and then dunk it in a "never the same" mixture of chemicals to reproduce the image. Even the drying process is random. The result is one of many versions of the image that I made with a fairly precise data gathering machine, never to be repeated precisely again. One might be able to argue that a dot matrix printer is also a randomizing machine that makes random prints. I would argue that the "wet print" is orders of magnitude more randomized than todays printers are... and much, much, more alive...

[bob carnie]

There are many here who teach digital negatives, currently the best in my books is my buddy Sandy King, I have learned hundreds of tips from him, he is also responsible for teaching me carbon , but as well
from that teaching helping me conclude that carbon is not a process for me. Sorry Sandy I like gum printing.

I am particularly interested in Sandy's profile making ability's with a spectrometer to tailor make curves and profiles for process. I do not think we are there yet but there may come the day
when the new inkjet systems will not work well with the digital neg systems and there will be a void to say the least.
This is a very interesting step forward IMO.

For me I am making my negatives over the next few years via a Lambda and Silver Ortho film, the ability to create good profiles to apply for each and every process will be very important to me and I will
be asking for help from people like Sandy.

I think we can all agree that having a good starting point where the Pt Pd print is spot on with the first print is an incredible step towards creative freedom. By custom mixing some developers and use of density to
make the second print magical is really fantastic.

I remember the work that went into colour correcting RA4 , I remember the work making enlarger negatives and then subsequent PT PD prints, this trial and error is now lessened with good profiles.


Michael - you are seeing the magic of a wet print, the very thing that hooks many of us for a lifetime of trial and error, I find it to be a lot of fun.