Salted paper #2

[earlj]

Paper: Rives Lightweight White
Salting solution: 2% sodium chloride
Sensitizer: 12% silver nitrate solution applied with 1.5" wide hake brush
Image: Bridge between downtown Davenport, Iowa, and Rock Island, Illinois
Print Exposure: spiral BLB compact fluorescent bulb, 1 hour, 20 minutes
Attached files http://f295.f295.org/uploads/saltdavenportrockislandbrid_7614.jpg (http://f295.f295.org/uploads/saltdavenportrockislandbrid_7614.jpg)

[staft]

fruit flies like a banana and earl j likes a bridge- and knows what to do with one. is a salt print similar to salting watercolor paper- a pocking texture? or just salts in the chemistry?

[earlj]

Silver chloride is insoluble in water, so the chloride has to be applied separately from the silver if it is not deposited in a dispersion like gelatin. I dissolved 20 grams of plain pickling salt (non-iodized sodium chloride) in a liter of water. I soaked the paper in this solution and then allowed it to dry. I also prepared a silver nitrate solution (12 g in 100 ml). When it is time to print, I brush the silver nitrate solution onto the salted paper and let it dry in the dark. I then make a contact print in my home brewed contact frame either in the sun, or with my hokey spiral BLB fluorescent lamp. It is a printing out process, so you can see when to stop exposing. Then, the print is washed in water to remove the excess silver, fixed in plain hypo that is slightly alkaline to prevent bleaching, treated to a bath in hypo clearing agent, and then washed in water. It's pretty easy to do, but there are so many variables that it is taking me awhile to master it.

[ImageMaker]

That print makes it look easy, Earl. Now I'm *definitely* going to have to get some silver nitrate with my chemical order, if I can afford any. Let's see, 12% solution, so 100 grams would make about 800 ml of solution, and it'll take about 1/2 to 3/4 ml to brush sensitize a 4x5. I guess it's not *that* expensive (given that non-iodized salt is *really* cheap and watercolor paper isn't too bad), once you get over the buy-in price of the silver nitrate (which I can also use for van Dyke, of course, plus albumen and satista if I ever get that far).

The finished prints ought to have similar longevity to silver gelatin, especially if toned, and aren't subject to some of the bad stuff that can happen to gelatin in marginal storage (though fungi can grow on paper just as readily as on gelatin, at least it won't glue itself permanently to the next sheet if it gets a little damp).

Have you experimented yet with overprinting and bleaching back? I understand a lot of printers do that with salt prints and van Dyke (though Farmer's Reducer is probably better for the bleach-back than, say, acid rapid fixer).

[gneissgirl]

So-o-o-o beautiful! As if the photograph alone weren't fine on its own, the process really brings it home. The color is gorgeous. Are the two prints really different hues (part of the serendipity of alt processing), or is it just the scanning/monitor translation that makes them seem different? Both are lovely.

[Carl Radford]

Works well Earl - something I've yet to try!

[moot]

Nicely done, Earl! Looks like you nailed the tonal range very well on this one.

[earlj]

Have you experimented yet with overprinting and bleaching back? I understand a lot of printers do that with salt prints and van Dyke (though Farmer's Reducer is probably better for the bleach-back than, say, acid rapid fixer).

So far, I am only trying to get the basics down. For some reason, salt prints seem easier to get repeatable results than cyanotype for me. I think that the main reason is speed - the coating dries faster, the exposures are shorter, and the wash time is less (if you use hypo clear). I want to try reducing/bleaching, and I also want to try toning. I have tested very weak selenium toner, but I did not like the way that it darkened everything, including the highlights. Perhaps a combination of toning and bleaching is in order. Would the bleach that comes with sepia toner work on these prints? I would think so - silver is silver.

Albumen prints are essentially the same process, only the paper is sized with treated egg white before sensitizing, so I should be ready to try that next.


The color is gorgeous. Are the two prints really different hues (part of the serendipity of alt processing), or is it just the scanning/monitor translation that makes them seem different? Both are lovely.

Thanks, Mary. The color of salt prints is an interesting topic when you start to read up on it. The grains of silver are so small, that the light reflected depends on a lot of factors. The absorbency of the paper is the most important (not the color, as you might think). The less the paper absorbs, the more orangish the color of the final product. A lot of the 19th century salt prints look almost red - I think that they were using highly sized paper that absorbed very little of the sensitizer.

I have been trying to defeat all of the automatic options on my scanning software so you guys can see what I see. But, as is always the case, the paper products look better than the scans.

I am not sure that I like the heavier texture of this Rives paper. I think that so far, anyway, I am most fond of the harder surface papers. I will have to search for even smoother, less absorbent paper. Any experience out there with sizing with arrowroot or cornstarch?

[ImageMaker]

Let use know what you find, Earl. I've been trying to find (albeit not yet with much concerted effort, due to circumstances) a suitable paper with a hard, smooth surface more or less like posterboard; perhaps not as glossy, but in that range. And, of course, it has to stand up to being soaked in water for a relatively long time during fixing and wash.

BTW, I wonder about the utility of hypo clearing agent for this process -- as I understand it, it aids the diffusion of complexed thiosulfate (i.e. carrying the dissolved silver) out of the gelatin in conventional film and prints, but there's no gelatin involved in salted paper (unless you apply it as sizing, of course). Do the authorities give any indication why they recommend it?

[earlj]

IM:

This is from the Reilly Salted Paper and Albumen book:
http://albumen.stanford.edu/library/monographs/reilly/chap9.html

"Washing of Prints
GENERAL CONSIDERATIONS
The purpose of washing is to remove the sodium thiosulfate and silver thiosulfate complexes that remain in the print after fixation. Over the years a great deal of attention has been paid to the theory and practice of washing photographic materials, but insufficient washing still remains a leading cause of the deterioration of photographs. The washing of photographic prints is more difficult than the washing of films, primarily because of the absorption of thiosulfate into the paper fibers. With prints the rate of washing slows down tremendously at the lower levels of thiosulfate concentration,8 and in practice it is impossible to remove every trace of thiosulfate simply by washing in water.

In the case of albumen and salted papers, effective washing is even more important than in modern photographic materials. In the older papers, the silver image is in much more intimate contact with the paper fibers than is the case with modern papers, where a substratum of baryta and gelatin (or polyethylene) separates the image layer from the paper base. Therefore, with albumen and salted papers a combination of both proper fixation and effective washing is necessary to insure that the base paper does not become a reservoir of image-threatening substances. It is very important in this regard that immersion of the prints in the fixing solution is not prolonged beyond the recommended time. Experimental evidence on the washing of albumen and salted paper prints is almost nonexistent. However, the factors which affect the rate of washing gelatin prints are probably valid for these papers as well.

The removal of thiosulfate from prints cannot be accomplished simply by washing in water, if a print of optimum stability is desired. In fact, water is such a poor remover of low levels of thiosulfate from prints that an extra step in processing is needed to assure maximum print permanence. This consists of treating the prints in a so-called "washing aid" or hypo clearing agent in order to facilitate more complete removal of the thiosulfate. These treatments are effective because they displace the absorbed thiosulfate ions and replace them with less harmful and more soluble ions of various salts. The best "washing aid" for albumen and salted papers consists of a 1% solution of sodium sulfite, although proprietary formulas such as Kodak Hypo Clearing Agent may also be used."

Does this answer your question?

[buggy]

Wow! Very nice.

[buggy]

Earl, This image is very beautiful and the tone wonderful. I don't know your level of expertise but you are making some very fine prints.

To achieve more image permanence you could tone the prints using gold, platinum or palladium toner. The silver will, over time, oxidize. However, if you tone with one of these noble metals you could potentially achieve permanence into the centuries, assuming the prints are taken care of. The toning metal will replace the silver thus eliminating silver oxidation. Also, to achieve full replacement, or nearly full replacement, toning must be done in the 10-15 minute range. Selenium toner will also give more permanence. The toning must be done before the fixing stage, except with selenium.

It is just a thought that you might want to consider. You certainly don't need to tone to achieve a particular color because your prints are beautifully toned the way they are. But if you are concerned about image permanence it might be something to consider.

[buggy]

Oh, another thing. Thanks for the info on washing prints. I have not been using hypo clearing as I thought a long enough (50 minute) water wash would do the trick. I will now add a clearing step just to make sure. Thanks.

[ImageMaker]

Does this answer your question?


Yep, that just abour covers it. :)

[earlj]

Have you experimented yet with overprinting and bleaching back? I understand a lot of printers do that with salt prints and van Dyke (though Farmer's Reducer is probably better for the bleach-back than, say, acid rapid fixer).

I have been reading up on this subject, and it looks like Farmer's Reducer is potassium ferricyanide and sodium thiosulfate, both of which I happen to have on hand. From what I have been able to read, if you keep the two solutions separate, you can go back and forth between them, alternately reducing some of the silver grains and then removing them with the hypo. This seems to work as a proportional reducer (working first on the highlights) when the solutions are separated, and works as a cutting reducer (reducing all areas at once) when mixed and treated in one tray. It sounds similar to the method that I used with the sodium carbonate and the tannic acid on the cyanotype that I toned. I think that this image could have used some brightening of the highlights without removing any density from the shadows. I will give it a try the next batch of salt prints that I crank out.

[cnmne]

Intriguing process and image -- both suit each other very well.

[Marv]

This is a really nice image Earl. Somewhere along the line I missed it when you posted it.

The process and your composition make me think this was done in 1906, not 2006.

The link to the Reilly Salted Paper and Albumen book looks helpful too.