Arches Aquarelle?

[revdoc]

I generally don't see what I'd call "fizz". Typically I see anything from a few bubbles to a dozen, on a 10x11 sheet. It varies quite a bit. If I look carefully I can see the bubbles growing before they break away. Sometimes they can be hard to shake off by rocking the tray.

Overall, I think the bubbles you saw were from the buffers. If your prints don't show spots or blotches, you can assume the job was done.

 

[revdoc]

"alkaline reserve" might not be composed of a carbonate that generates carbon dioxide when treated with acid.

I also thought that might be the case, so I checked the Arches web page linked. The words "alkaline reserve" link to a popup that says "calcium carbonate". Mind you, the web site might not tell the whole story.

 

[MurrayMinchin]

Your 'no fizz' result strongly suggests that Arches Aquarelle does not contain a carbonate buffer. Have you tried an exposure on the paper as you received it?

Also, why are you coating the back side? Some papers have two very different surfaces. I suggest that you try coating the front side as well just to see what happens.

As shown by others in the last couple posts, the company says it does contain calcium carbonate.

The two prints made today were on paper straight from the watercolour pad...no pre-acidification at all. The second one, which was double coated with silver, is deeper at the dark end of things but I also added more gold to the toner it received.

Spit-balling theory: sizing on both sides is protecting the sensitizer from the bulk of calcium carbonate? Company also claims the paper has “sizing to the core” which might also come into play?

Why the backside? Both sides have sizing, and I wanted to see what a 'bit of' texture looked like before trying the nubbly front side. There are no rules

I'll post a photo tomorrow.

 

[nmp]

Spit-balling theory: sizing on both sides is protecting the sensitizer from the bulk of calcium carbonate? Company also claims the paper has “sizing to the core” which might also come into play?

Not a bad theory. It might also mean then that the presence of buffer is unlikely to interfere with the salt chemistry and you would be fine not neutralizing it. I guess if your pints come out OK (Dmin's at paper white or close) then all is good.

:Niranjan.

 

[MurrayMinchin]

Here's a quick digi-snap of yesterdays step tablet (Clay Harmon's) using Arches Aquarelle. Paper came from a 9x12 300gsm watercolour pad, with no pre-acidification treatment. It's a fairly accurate representation. Used 4 lights on a DIY copy stand, so the texture isn't emphasized in this photo.

One coat of 2% salt and two coats 12% silver nitrate, toned in a gold borax toner. Sequence: 10 minutes in 4 changes of water, 30 seconds dilute salt bath, 5 minutes toner, 4 minute wash, 4 minute first fix, 4 minutes second fix, 4 minute wash, 4 minutes HCA, 30 minute wash. Believe it or not, the toner did take away quite a bit of warmth.

Used a manual salt curve I came up with for HPR. The first one was weak in the dark areas, so this one got a double coat of silver and increased the negatives density by changing Epson's ABW from 'Light' (which I was using for HPR) to 'Normal' as a stab-in-the-dark attempt at a good dark tone and maybe luck out with the high tones. Kept the same exposure time as HPR.

I like what I'm seeing in terms of colour and texture, so will continue playing with this paper.

...I guess if your pints come out OK (Dmin's at paper white or close) then all is good.

:Niranjan.

Looking at what is supposed to be the 'max white' border along the tablets edges, it appears to be fogged a bit...is this an indication that pre-acidification is required? Will try that today or tomorrow, just to be sure.

 

[MurrayMinchin]

Just in case someone is following along, or stumbles across this thread in the future:

"It is not uncommon for advanced platinum / palladium printers to slightly acidify different types of paper in order to prevent an acid-base (alkali) reaction that occurs when an acidic ferric oxalate comes into contact with a buffered alkaline paper. The first thing you will want to do is verify whether or not you have an alkaline paper and this is easily accomplished by reading the manufacturers production specifications or testing the paper with a pH Testing Pen which is easily obtainable on many Internet chemistry sites. Don’t assume that because the manufacturer sates the paper is neutral pH that it is. A simple truck shipment through any metropolitan area in high heat and humidity can change that claim in a hurry. A simple method of acidifying your paper if it is alkaline is to make a 2% citric acid solution and to soak or brush coat it on your paper. If soaking, allow 1 to 3 minutes, rinse for 10 minutes, and then allow the paper to dry overnight.

If you don’t happen to have any citric or the more recent but untested favorite, oxalic acid, around the house, use straight household vinegar for 2 minutes, wash for 10 minutes and hang to dry overnight before using. This vinegar pre-acidification (or de- calcification) works best with Fabriano and Cranes papers when you are using an ammonium citrate developer. In all acid bath situations, watch the surface of the paper during a soaking or brushing with an acidic solution. Surface sizing may begin to fall away from the paper and this is not what you want."

https://www.christopherjames-studio.com/platinumPalladium3rdEdBookOfAltPro.pdf

 

[nmp]

Looking at what is supposed to be the 'max white' border along the tablets edges, it appears to be fogged a bit...is this an indication that pre-acidification is required? Will try that today or tomorrow, just to be sure.

That might help. Also noticed you are not using any citric acid. Perhaps you didn't need it on HPR, but might be useful here. That would be my first line of defense - I'd rather not do acid treatment if I don't have to. Also, does it look like the shadows from 92-100% are kind of clumped up. Exposure time could be shorter? That might cut the fog somewhat too.

:Niranjan.

 

[MurrayMinchin]

That might help. Also noticed you are not using any citric acid. Perhaps you didn't need it on HPR, but might be useful here. That would be my first line of defense - I'd rather not do acid treatment if I don't have to. Also, does it look like the shadows from 92-100% are kind of clumped up. Exposure time could be shorter? That might cut the fog somewhat too.

:Niranjan.

Thanks...will definitely chip away at all your suggestions

 

[MurrayMinchin]

...Also noticed you are not using any citric acid. Perhaps you didn't need it on HPR, but might be useful here...

:Niranjan.

Hi again.

I've been using Ellie Young's book, The Salt Print Manual. She mentions citric acid in arrowroot sizing and in Pt/Pl toners.

Are you suggesting citric acid for neutralizing calcium carbonate (like adding it to the salt solution?) or somewhere else in the process?

 

[nmp]

Hi again.

I've been using Ellie Young's book, The Salt Print Manual. She mentions citric acid in arrowroot sizing and in Pt/Pl toners.

Are you suggesting citric acid for neutralizing calcium carbonate (like adding it to the salt solution?) or somewhere else in the process?

OK...I don't even remember where I saw the use of citric acid first. It's not in Young's book - you are right. Also not in O'Reilley. Might have been James. Most people add CA to the silver nitrate (to the ratio of 1:2 resp) just before coating. Say you are using 12% silver, then actually make 24% silver solution and a 12% CA solution and then mix equal drops of each. I found it a little cumbersome to make this mixture (some make a 40-50% solution and add a drop or two like how T-20 is done,) so I have started using the CA in the salt solution recently - it is easier as you can keep the solution unlike in silver where it will precipitate silver citrate over time in the bottle. Salt solution is then 2% NaCl + 6% CA.

Use of CA in this context is not so much as countering the buffer - although it might do that as well. But even in un-buffered papers, it can work to improve the Dmin - both by suppressing the "dark" reaction (as a preservative) and cleaning up the 0 step. I do see these benefits on COT 320, both when added to the silver and added to the salt. But like anyhting in alt world, YMMV.


:Niranjan.

 

[MurrayMinchin]

OK...I don't even remember where I saw the use of citric acid first. It's not in Young's book - you are right. Also not in O'Reilley. Might have been James. Most people add CA to the silver nitrate (to the ratio of 1:2 resp) just before coating. Say you are using 12% silver, then actually make 24% silver solution and a 12% CA solution and then mix equal drops of each. I found it a little cumbersome to make this mixture (some make a 40-50% solution and add a drop or two like how T-20 is done,) so I have started using the CA in the salt solution recently - it is easier as you can keep the solution unlike in silver where it will precipitate silver citrate over time in the bottle. Salt solution is then 2% NaCl + 6% CA.

Use of CA in this context is not so much as countering the buffer - although it might do that as well. But even in un-buffered papers, it can work to improve the Dmin - both by suppressing the "dark" reaction (as a preservative) and cleaning up the 0 step. I do see these benefits on COT 320, both when added to the silver and added to the salt. But like anyhting in alt world, YMMV.


:Niranjan.

Ahhhh, thanks for the clarification...really appreciate the time it takes to answer.

I gave todays paper a 3 minute soak in 2% citric acid with a 10 minute wash this morning. Also shortened the exposure like you suggested in post #57, from 12 minutes to 10 minutes. Used the same salt curve negative as the previous print, with identical coating, processing and toning. So far (in the final wash) it looks waaaay better. Much cleaner white.

Experience is adding up...it took 3 prints to get a pretty good result with this paper, but it took a lot more starting from absolutely no experience with alt processes (and making digitally enlarged negatives) a couple months ago.

When you change something it's like pulling on one point of a spiders web...every other point shifts in response. Good thing I'm retired!!!!

 

[MurrayMinchin]

Here's the one from earlier today; the one that got the decalcification citric acid bath and then dried before coating. Photo is a fairly good representation, but nowhere near precise! (The white is overly warm in an attempt to get the gray tones to look something like the print).

Looks like you were right, Niranjan...the dark tones got some separation with reduced exposure.

Much less warmth than the last one, has smoother grain structure overall, has less 'fogging' in the white border of the step tablet, and the lightest square is closer to paper white.

Will do a max black test next, because it might need another minute or so of exposure. Will also probably make another negative and go from either Epson Advanced Black & White 'Normal' to 'Dark' density, or stay at 'Normal' and add 75 yellow.

Being pretty loosey-goosey at this early stage...laying a base for what I hope may become an intuitive level of understanding. Also, haven't settled on a paper yet and intend to tone in either platinum, palladium, or a combination of both once things get serious.

 

[nmp]

Here's the one from earlier today; the one that got the decalcification citric acid bath and then dried before coating. Photo is a fairly good representation, but nowhere near precise! (The white is overly warm in an attempt to get the gray tones to look something like the print).

Looks like you were right, Niranjan...the dark tones got some separation with reduced exposure.

Much less warmth than the last one, has smoother grain structure overall, has less 'fogging' in the white border of the step tablet, and the lightest square is closer to paper white.

Will do a max black test next, because it might need another minute or so of exposure. Will also probably make another negative and go from either Epson Advanced Black & White 'Normal' to 'Dark' density, or stay at 'Normal' and add 75 yellow.

Being pretty loosey-goosey at this early stage...laying a base for what I hope may become an intuitive level of understanding. Also, haven't settled on a paper yet and intend to tone in either platinum, palladium, or a combination of both once things get serious.

Wow...that is a great improvement. I like the tone better here, almost like eggplant and the highlights look more cheerful. Most of all, the grain and surface imperfections in the earlier print are nearly gone - I wonder if one of the side effect of doing the acid treatment is homogenizing the surface chemistry/physics somehow. Perhaps just the act of washing is responsible for this change - irrespective of the pH. Might be worthwhile to do this even if you don't need the buffer neutralization. I sense a set of experiments coming...

Thanks for sharing!

:Niranjan.

 

[MurrayMinchin]

Wow...that is a great improvement. I like the tone better here, almost like eggplant and the highlights look more cheerful. Most of all, the grain and surface imperfections in the earlier print are nearly gone - I wonder if one of the side effect of doing the acid treatment is homogenizing the surface chemistry/physics somehow. Perhaps just the act of washing is responsible for this change - irrespective of the pH. Might be worthwhile to do this even if you don't need the buffer neutralization. I sense a set of experiments coming...

Thanks for sharing!

:Niranjan.

The colour shift is amazing. In the initial water wash it appears to be made of cranberry with a dash of beets, changes a bit in the toner, a bit more in the fix, then radically swings to the cooler end of things as it dries.

Very much has the feel of a boiling cauldron, eye of newt & toe of frog, swirling mists and phantasmal visitations.

Just made a new negative with a tweaked curve. Lifted things from about middle grey to paper white in hopes of getting more distinct steps in that region and paper white on the first step. (Will put a small piece of rubylith tape over the brush strokes to see if the paper is clearing). Also messed around with the toe area in hopes it will result in a smoother launch from max black, with a bit more separation in the lowest tones. Kept the same 'Normal' density in Epson's ABW, but added 75 Yellow.

Next print will have the same citric acid & processing as the last one, but will get one more minute of exposure. Hopefully it's a keeper!

 

[MurrayMinchin]

Update.

Finally got the highest tones under control, having them land exactly where I wanted, but lost control in the low tones. One more adjustment to the curve should do it. It's only been 14 tries...so far..........

Had enough with step tablets, so tried a print of my go-to test image that has delicate whites, subtle clouds, mid tone areas, textured shadows and a couple spots that are supposed to be max black. On a whim, tried 2% citric acid bath for 4 minutes with a 10 minute wash & dry before coating. It came out 'weird' and grainy. It was at the end of a loooong day, but I'm pretty sure I did all the steps correctly. The scan is also too purple, but I can't fix it without it looking even weirder.

Another thing is that the whites never got to 100% paper white. When I put a piece of ruby lith tape over a part of the border, there was a barely perceptible yellow-ish amber-ish tone...something like subtle plate tone on a photogravure.

Think I'll go back to Hahnemuhle Platinum Rag for a while, get myself firmly planted in the salt print realm, then try buffered watercolour papers some time in the future. No wasted effort, much was learned

The second photo shows the high tones. The goal is to get white lines on the overturned dinghy hull to show, and for threshold tones above the gunnel on the boat to the left. Very happy with this result. Things sure get twitchy at the top end!

There's a person in the foreground boat who's pants are supposed to be max black and the sweater is supposed to be a barely discernible dark grey. If the dark tones had landed lower where they should have, the print would have had some pop & sizzle. As it is, it's a dud.

Will put some Renaissance Wax on this print to see what happens and post that later.