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Michael Lloyd
27-Jul-2016, 16:17
The following three images were made at Don Messec's Making Art Safely Platinum printing workshop that I took last week. The negatives were created from digital prints using the new PiezoDN system from Jon Cone of Inkjet Mall. By now most people are familiar with his Piezography inks. PiezoDN is the newest iteration of that. Once the negative is made and dried the Platinum process isn't any different than the historic process. Hopefully this is ok here.

Scanning is kind of hard on the prints imho but these are close. They are the first platinum (or wet for that matter, not counting when I was about 8) that I've made. The process of learning has begun

153293

153294

153295

koraks
28-Jul-2016, 01:20
If these are your first tries and the scans are a faithful depiction of the real prints, then I'd say there's very little room for improvement - if any at all! They look perfect to me.

Randy Moe
28-Jul-2016, 04:13
Nice work!

Michael Lloyd
28-Jul-2016, 04:31
The scanner (Epson 10000XL) isn't "color managed" but the monitor (color managed) and print look pretty close when I put the print beside it. The monitor is a little darker but not much

During the course of the workshop (5 days) we dialed in the process of making the negative, coating the paper, and making the print. In my case I brought my little Epson 1430 printer and dialed it in too. I also brought my tabletop exposure unit and dialed it in. The PiezoDN system is fairly new and Don chose to show us that rather than "last year's" method of making a negative so there was a little time spent on that. We learned to brush rather than use a coating rod. I made 3 versions of the first one (pier) and the scan is the third version from the final day. The other two have one previous version and the scans are from the final day. Once you get a good negative, paper coating, and exposure correct the print is the reward. Sounds like photography doesn't it?

I was never very good with film but I always enjoyed using the camera. Other than a brief experience with a Sears-Roebuck darkroom kit when I was a kid I haven't had the pleasure of working in a darkroom. Then digital came along and rekindled my interest in photography. I got pretty manic about learning to make a good digital print and spent about 5 years and a couple of dollars on workshops for that. But this... making a wet print... is the best experience I've had with photography. I like the digital negative process but I think my 4x5 and 5x7 will be seeing more use too...

Thank you. It was a lot of fun

Christopher Barrett
28-Jul-2016, 08:01
Very cool. I'm doing a similar workshop in two weeks at Renaissance Press. Really looking forward to it!

joncone@cone-editions.com
29-Jul-2016, 13:58
Hi Michael,

Was Don able to teach you how to use my PiezoDN system to make Pt/Pd prints that match your screen display? Did you do the ICC portion of the process that matches screen gamma?

best,

Jon


The following three images were made at Don Messec's Making Art Safely Platinum printing workshop that I took last week. The negatives were created from digital prints using the new PiezoDN system from Jon Cone of Inkjet Mall. By now most people are familiar with his Piezography inks. PiezoDN is the newest iteration of that. Once the negative is made and dried the Platinum process isn't any different than the historic process. Hopefully this is ok here......

D. Bryant
29-Jul-2016, 15:25
The following three images were made at Don Messec's Making Art Safely Platinum printing workshop that I took last week. The negatives were created from digital prints using the new PiezoDN system from Jon Cone of Inkjet Mall. By now most people are familiar with his Piezography inks. PiezoDN is the newest iteration of that. Once the negative is made and dried the Platinum process isn't any different than the historic process. Hopefully this is ok here.

Scanning is kind of hard on the prints imho but these are close. They are the first platinum (or wet for that matter, not counting when I was about 8) that I've made. The process of learning has begun



So you are making pure platinum prints? Or a mixture of palladium and platinum. What kind of paper did you guys print with?

Michael Lloyd
29-Jul-2016, 16:57
Hi Michael,

Was Don able to teach you how to use my PiezoDN system to make Pt/Pd prints that match your screen display? Did you do the ICC portion of the process that matches screen gamma?

best,

Jon

We did everything but the ICC profile Jon. There was an issue with part of it that I didn't quite follow. Don and Walker were working through it. But that's a good point, the scans I posted aren't as good as they could be (very close though) because the last step (ICC profile) wasn't completed.


[QUOTE=Michael Lloyd;1342400]The following three images were made at Don Messec's Making Art Safely Platinum printing workshop that I took last week. The negatives were created from digital prints using the new PiezoDN system from Jon Cone of Inkjet Mall. By now most people are familiar with his Piezography inks. PiezoDN is the newest iteration of that. Once the negative is made and dried the Platinum process isn't any different than the historic process. Hopefully this is ok here.

Scanning is kind of hard on the prints imho but these are close. They are the first platinum (or wet for that matter, not counting when I was about 8) that I've made. The process of learning has begun

TEQUOTE]
B
So you are making pure platinum prints? Or a mixture of palladium and platinum. What kind of paper did you guys print with?

Apologies. Yes, Platinum Palladium. Bear in mind that Don's business is called Making Art Safely. So the developer wasn't heated. We used the safest formulations that we could. You'll know what this means without explanation:

Pd - 26
Pt - 6
Fe#1 - 32
Tween - 1

Paper: Arches Platine, 2006 paper not last years paper. I have a box of 8.5 x 11 Arches Platine that I bought last year. I wish I had bought the earlier version (more texture) of the 22x30 but I am in no way disappointed with the Arches Platine I used and have now ordered in 22x30.

Vaughn
30-Jul-2016, 09:31
What type of camera was used to create the the original image?

Michael Lloyd
30-Jul-2016, 09:52
What type of camera was used to create the the original image?

It was 35mm DSLR (digital). I have a 5x7 and 4x5 and plan to make contact prints but I don't have a negative that I like well enough to try the process. Yet. Even then, I will scan the negative and create a negative from the digital file.

stawastawa
31-Jul-2016, 12:42
lovely prints! very rich and expressive.

Would you share some of what makes the process "safe".
My understanding is working with pt/pd is fairly toxic, especially as you use additives for exposure control.

Michael Lloyd
31-Jul-2016, 13:07
lovely prints! very rich and expressive.

Would you share some of what makes the process "safe".
My understanding is working with pt/pd is fairly toxic, especially as you use additives for exposure control.

Thank you,

As you wrote, "safe" does need to be in quotes. Safer is probably a better way to term it. For instance, the developer wasn't heated. Patrick Alt (and probably many others) used a Bunn coffee warmer to heat the Ferric Oxalate developer to promote higher contrast as I understand it. In an unventilated space that could cause problems. He also used muriatic acid in his first two clearing baths. We used water. Then hypo clear. Then water. We didn't dry the prints with a hair dryer. They were air dried. It's little things and having the understanding that the metals and developer have to be used and stored properly.

One of the guys in the workshop had no idea about the process. He was a digital and film photographer that had no inkling of what the darkroom was about. Or in our case dimly lit room. On the first day he wanted to know which Epson paper we were going to use. I'm not making fun of him in the least bit, he ended up making some gorgeous prints and I'm confident that he didn't contaminate himself in any way. It was an education about the process of how to make a platinum print as safe as it can be done.

stawastawa
31-Jul-2016, 21:34
Thanks michael,
I have never worked with PT/PD before but am interested. I assume that in mixing and working with coating the emulsion has a smell to it, is that so?


Thank you,

As you wrote, "safe" does need to be in quotes. Safer is probably a better way to term it. For instance, the developer wasn't heated. Patrick Alt (and probably many others) used a Bunn coffee warmer to heat the Ferric Oxalate developer to promote higher contrast as I understand it. In an unventilated space that could cause problems. He also used muriatic acid in his first two clearing baths. We used water. Then hypo clear. Then water. We didn't dry the prints with a hair dryer. They were air dried. It's little things and having the understanding that the metals and developer have to be used and stored properly.

One of the guys in the workshop had no idea about the process. He was a digital and film photographer that had no inkling of what the darkroom was about. Or in our case dimly lit room. On the first day he wanted to know which Epson paper we were going to use. I'm not making fun of him in the least bit, he ended up making some gorgeous prints and I'm confident that he didn't contaminate himself in any way. It was an education about the process of how to make a platinum print as safe as it can be done.

Michael Lloyd
1-Aug-2016, 05:55
Thanks michael,
I have never worked with PT/PD before but am interested. I assume that in mixing and working with coating the emulsion has a smell to it, is that so?

I don't have a recollection of anything that smelled, good or bad. It's a very relaxing process once you learn it

The Pt and Pd are premixed. If you were to mix them yourselves you would probably need all kinds of permits. Separately they are very bad (I'm told).

Contrast agent, Fe #1 in our case, came as a powder in a bottle. Add warm distilled water and shake, and shake, and shake... it doesn't dissolve easily.

Tween is a surfactant and it comes premixed. I doubt if it would be hard to make but I don't know for sure what's in it.

Developer, Potassium Oxalate, comes as powder. Mine came in 1L jugs. I also have a 1000g bulk container but the 1L jugs will last me quite a while. It doesn't go "bad" you just keep adding to it. To make it, I just added warm distilled water and shook it a little. Coating paper and developing were both great experiences.

Here's a link to #1 of 3 YouTube videos (watch all three) -


https://youtu.be/pdJ7yPqNWyw

Bear in mind that the PiezoDN system is a digital negative creating system that is not constrained to just making Pt/Pd prints. It's a system for refining negative quality for use in alternative processes. You can scan your film negative, edit it, and then recreate the negative (larger or smaller than the original) with the PiezoDN system. They are working on a silver negative process.

Search YouTube for- Platinum printing on Tosa Washi Platinum Paper (Japanese Tissue)
The man has skills...

Vaughn
1-Aug-2016, 07:19
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.

Michael Lloyd
1-Aug-2016, 07:36
One of the class participants tried Ammonium citrate on one of his portraits. I didn't like the result. Of course everything can be tweaked but I thought it lacked contrast. If I was printing a snowscape I might consider it.

"The process itself is neither safe or unsafe". Agreed. The workshop was about the chemistry and how to minimize exposure to oneself and the environment. I can't really speak to what is and isn't hazardous beyond what we learned in a 1 week printing class. We discussed how adding EDTA to the developer could increase the "hazard". I picked up a copy of OverExposure, Health Hazards in Photography. The author does a pretty good job of spelling out the hazards of the chemicals that are used in alternative processes.

Good point about using a blow drier.

I bought all of my supplies from Bostick and Sullivan. Unfortunately I didn't get to visit their store when I was in Santa Fe. Maybe next time.

bob carnie
1-Aug-2016, 07:47
Nice Video by Tony H- I have followed his work here in Toronto since the 70's he is a super nice guy.

Michael Lloyd
1-Aug-2016, 08:04
Nice Video by Tony H- I have followed his work here in Toronto since the 70's he is a super nice guy.

I enjoyed his subtle sense of humor. His video is what kicked me off on this adventure a few years ago...

bob carnie
1-Aug-2016, 08:42
Tony is a very fun guy to be around, he is extremely gracious with everyone he meets. He is the only photographer that I am aware of in the Toronto GTA
who has carved out an excellent portrait business where silver gelatin and Pt Pd prints are what you get when booking him. He is coveted by the carriage trade that understands not
only quality but archival property's of the finished prints.
I look to his career as one that exemplifies the very best commercial photography in the portrait field, his work will be around for centuries and while thousands of other photographers
work is quite compelling , all of Tony's work will last and be a permanent record of Toronto People. He will definitely see the National Archives of Canada wanting his negatives and prints.

You couldn't have started off your adventure with a better person.


I enjoyed his subtle sense of humor. His video is what kicked me off on this adventure a few years ago...

Willie
1-Aug-2016, 10:21
Maybe the video is good. I can't tell. Sound bouncing around makes it impossible for less than stellar hearing ability to understand what is being said.

Vaughn
1-Aug-2016, 12:07
"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
1-Aug-2016, 12:34
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
1-Aug-2016, 15:02
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
1-Aug-2016, 17:39
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
2-Aug-2016, 05:51
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
2-Aug-2016, 12:58
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
2-Aug-2016, 13:37
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
2-Aug-2016, 13:37
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
2-Aug-2016, 18:25
"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
3-Aug-2016, 06:18
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.

sanking
3-Aug-2016, 08:12
Bob,

Gum is a great process for some people. I tried it myself many years ago, but eventually came to the conclusion that my vision is more photographic than painterly, and hand crafted processes like carbon and platinum work much better for me.

A good profile should help you to get to where the first print in process is good enough about 50% of the time, but in my work the perfect print nearly always needs two or three iterations by minor adjustments by contrast controls with the process. In carbon we have this both in making the print, and even after the print as it is possible to bring down density by soaking the print in very hot water for up to about a week after it is made. This post processsing density adjustment does not exist with pt/pd.

The key for me in making a great digital negative is the use of a RIP that allows control in terms of ink and percentage of ink deposited at every pixel point on the negative. QTR allows this, the Epson, HP and Canon drivers do not. I would suspect that there is a program somewhere that would give you this control with the Lambda.

BTW, I am tying to get set up to make some three color carbons for the first time in a couple of decades. With the ability to make digital separations and pin registration I am sure this will be much easier than in the past. I replaced the Stoesser punch and registration table you have with a similar one purchased from a company in British Columbia. Man, the Canadian dollar is so low it sure gives the buyer with a US dollar a big break in price.

Sandy

bob carnie
3-Aug-2016, 08:58
Gum is a great process for some people. I tried it myself many years ago, but eventually came to the conclusion that my vision is more photographic than painterly, and hand crafted processes like carbon and platinum work much better for me


Sandy

This is a great way to sum up Gum because my prints really look less like photographs with layers of gum. I am doing one hit gum over palladiums that look more photographic. But once you start putting three layers of gum well the image does transition to a different look.
Are you going to use the transfer of three colours to the paper like Bentley, I imagine there is no other way?? I have found that with four soakings of paper on aluminum the paper sometimes finally lifts off the support which is a pain in the ass.

my punch is working quite nice, btw use it every week.

Bob

Michael Mutmansky
3-Aug-2016, 09:57
HCl = Hydrochloric acid chemical formula

I think that the discussion above is using HCA as a reference to hypo clearing agent, but I've seen some people use HCA to mean Hydro Chloric Acid, so I wanted to be clear that people should not be using that stuff without proper attention to their health. It's volatile, so it gets in your lungs and eyes. It corrodes pretty much all metals, including stainless, so your plumbing will suffer, and while it does work for clearing, it is easy to overdo it and start bleaching if you aren't careful.

While it won't kill you like mercuric chloride, it is really too much risk for people to use without getting suited up, and who wants to do that in a darkroom.


---M

Vaughn
3-Aug-2016, 14:47
Question that has come up elsewhere...

What is the vapor pressure of Potassium oxalate? All I get in my searches is "not available". Does any Potassium oxalate actually rise up into the air from a hot bath of it? Or it is just water vapor?

Michael Mutmansky
3-Aug-2016, 16:56
Question that has come up elsewhere...

What is the vapor pressure of Potassium oxalate? All I get in my searches is "not available". Does any Potassium oxalate actually rise up into the air from a hot bath of it? Or it is just water vapor?

Not sure, but I believe some does get out. It has a slight odor.

Actually, that's not really clear either, since most PO is re-used, so you really have a witches' brew of FO, PO, metal salts, paper size, and who knows what else. I keep mine covered until the pour, and then back under cover after the print is out of it.

---Michael

Fr. Mark
4-Aug-2016, 09:51
Not having the right references in front of me to be sure of vapor pressure, but Potassium Oxalate is a salt of Oxalic acid, as with most salts its vapor pressure will be very low. Smell could be impurities or depending on what else is in the solution, the free acid. Oxalates have some toxicity, but I don't think it is as bad as cyanide. IIRC oxalic acid is the toxic agent in Rhubarb leaves (not stalks, the part I love for pie). People don't usually measure the vapor pressure of salts of organic acids. The value will be a really high number if the material doesn't decompose upon heating before liquifying let alone boiling. Oxalates will probably give off CO2 and CO (carbon dioxide, more/less harmless, and carbon monoxide, very toxic) upon degradation, but again, I no longer have the reference books at my finger tips.

HCl (hydrochloric acid, muriatic acid) is pretty corrosive even in low concentrations and concentrated solutions give off fumes that will sting the eyes and nose/throat if not outright burn them. I was reminded of this when adding acid to water (always do it that way not the other way around!) last night to make cyanotypes. I miss having a fume hood to do chemistry in. that said, I do not ban HCl from my basement. It's a very useful chemical. I'd suggest handling concentrated solutions with good ventilation, splash protection for the eyes and rubber (nitrile) gloves, but that pretty much applies to anything we use for photo chemistry and might not be a bad idea for some kinds of cooking of food! BTW conc HCl is 30-37% so when you have a 5% solution, it's still pretty strong even though 5% doesn't sound like much. True, it will eat stainless (it's stain less not totally impervious unlike the german Rostefrei (rust free---hah!)). But if you dilute it enough, it won't harm your pipes, particularly if you have PVC drain pipes which are pretty much impervious to dilute HCl. Stomach acid is a few percent, maybe even 10% HCl, as anyone with acid reflux will tell you, you want to keep that acid where the body is protected from it (the stomach, not the esophagus) but it isn't immediately dangerous to life with proper handling. Don't bathe in it, but don't overly fear it either. If I've used a lot of HCl, and I have iron and copper drain pipes, I will neutralize it with baking soda first to double "bomb proof" the dilution thing. This makes a lot of fizz (carbon dioxide) so use an over-sized container.

Fr. Mark
4-Aug-2016, 10:06
Sandy, is there someplace I can see the 3 color carbon prints? Also, why not 4 color separations? If you are going to climb that mountain, what's another layer to keep in registration etc etc (hahah)?

sanking
4-Aug-2016, 11:19
Sandy, is there someplace I can see the 3 color carbon prints? Also, why not 4 color separations? If you are going to climb that mountain, what's another layer to keep in registration etc etc (hahah)?


To be clear, I have not made any three-color carbon prints in a long time. At this point I am just trying to get set up to do it, which includes among other thing developing a three-color tissue set.

4-color separations are not needed to get blacks with high Dmax values in carbon as they may be for some graphic art processes.

Sandy

bob carnie
4-Aug-2016, 11:38
I look forward to seeing some of your progress, not for the feint of heart. but when they come out tri Gums they are wonderful I am sure your prints will sing.


To be clear, I have not made any three-color carbon prints in a long time. At this point I am just trying to get set up to do it, which includes among other thing developing a three-color tissue set.

4-color separations are not needed to get blacks with high Dmax values in carbon as they may be for some graphic art processes.

Sandy

Michael Mutmansky
4-Aug-2016, 12:49
Not having the right references in front of me to be sure of vapor pressure, but Potassium Oxalate is a salt of Oxalic acid, as with most salts its vapor pressure will be very low. Smell could be impurities or depending on what else is in the solution, the free acid. Oxalates have some toxicity, but I don't think it is as bad as cyanide. IIRC oxalic acid is the toxic agent in Rhubarb leaves (not stalks, the part I love for pie). People don't usually measure the vapor pressure of salts of organic acids. The value will be a really high number if the material doesn't decompose upon heating before liquifying let alone boiling. Oxalates will probably give off CO2 and CO (carbon dioxide, more/less harmless, and carbon monoxide, very toxic) upon degradation, but again, I no longer have the reference books at my finger tips.

HCl (hydrochloric acid, muriatic acid) is pretty corrosive even in low concentrations and concentrated solutions give off fumes that will sting the eyes and nose/throat if not outright burn them. I was reminded of this when adding acid to water (always do it that way not the other way around!) last night to make cyanotypes. I miss having a fume hood to do chemistry in. that said, I do not ban HCl from my basement. It's a very useful chemical. I'd suggest handling concentrated solutions with good ventilation, splash protection for the eyes and rubber (nitrile) gloves, but that pretty much applies to anything we use for photo chemistry and might not be a bad idea for some kinds of cooking of food! BTW conc HCl is 30-37% so when you have a 5% solution, it's still pretty strong even though 5% doesn't sound like much. True, it will eat stainless (it's stain less not totally impervious unlike the german Rostefrei (rust free---hah!)). But if you dilute it enough, it won't harm your pipes, particularly if you have PVC drain pipes which are pretty much impervious to dilute HCl. Stomach acid is a few percent, maybe even 10% HCl, as anyone with acid reflux will tell you, you want to keep that acid where the body is protected from it (the stomach, not the esophagus) but it isn't immediately dangerous to life with proper handling. Don't bathe in it, but don't overly fear it either. If I've used a lot of HCl, and I have iron and copper drain pipes, I will neutralize it with baking soda first to double "bomb proof" the dilution thing. This makes a lot of fizz (carbon dioxide) so use an over-sized container.

The problem is that almost no photographers have adequate ventilation and few have proper splash guards or respirators. The chemicals that most people are used to using in the DR are not really much of a concern, but HCl is a bit above that, and needs more respect than most DR people give their chemicals.

I use it very occasionally and in very small quantities, but I don't use it for a clear bath. That is introducing a lot of it in the darkroom where it sits in open trays, and there really are better ways to clear prints.

Oxalic acid is in rhubarb, spinach, and other 'bitter' greens like kale, etc. It takes a lot to ingest a lethal dose (8 pounds of spinach, if I recall correctly), so not really a concern, but it is a good enough excuse to avoid those things (if you needed a reason).


---Michael

Fr. Mark
4-Aug-2016, 18:59
Michael,

To each his own. Better safer than sorry, but I quite commonly have 8x10 trays of 1% HCl sitting out and have zero problems. I prefer to not open the bottle of conc. indoors.

Bob Mann
5-Aug-2016, 13:16
One of my "quick by eye" digital negatives - made using PS and a Canon Pro 10 printer. I didn't use any curves, just made a quick adjustment of black and white points. I do have a densitometer so I check the negative's ink density range, very similar to my method of working with a film negative. Printed on COT 320 with Na2 process - about 5x7 image size.

Aircraft radial engine cylinder head

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