View Full Version : Salt printing with Rodinal as a developer

25-Apr-2016, 07:48
Up to now have been making traditional Salt prints. Then I bought a book SALT PRINT by Peter Mrhar. He described another technique for developing salted prints which seems to be "now almost unknown".

1. Paper sensitized with an emulsion formula with the addition of citric acid
2. Expose print for 1/3 standard printing time
3. Immersed and develop in a 1% solution of Rodinal for 5 minutes.
4. Wash for 3 minutes
Fix, wash, clearing agent, final wash

Has anyone else used this technique? The toning step is not used but replaced by the Rodinal development.

Tin Can
25-Apr-2016, 08:13
All I have done is read extensively about Salt Prints.

This sounds interesting.

We await your results. :)

25-Apr-2016, 09:55
Haven't tried it, but I might! To get it straight: no initial rinse before developing the print?
What is the supposed advantage of this work flow? I can sort of imagine that it would result in a more neutral tone a d perhaps higher contrast, but does the source say anything about it?

Tin Can
25-Apr-2016, 12:24
I bought that Kindle book. Peter is the man. Try it.

27-Apr-2016, 16:37
Just got my Arista UV lightbox in from Freestyle Photo. Have to tun tests to get my standard printing time for my digital negatives. Then most probably will have to recalibrate the scale of my digital negatives a little bit. Finally make a few good final salt prints.

The will try to develop with Rodinal... certainly seems will be a lot cheaper alternative than using a Gold toner. The "exposing for 1/3 of the standard printing time" seems to be a possible variable. Will have to run 1/4, 1/3, and 1/2 of standard printing time tests. Processing in a 1% solution of Rodinal for 5 minutes at a standard temperature (68 degrees) fortunately can easily be standardized. May take a few weeks, but will post the results on this Forum.

Sidebar: I live in Collinsville Connecticut and am very active in out town's historical Museum. Charles Harrington was a photographer in town who owned and ran a Pharmacy and Photo supplies store. He prolifically photographed around our town from approximately 1890-1915. Used 4x5, 5x7, and 8x10 glass plates. We have a collection of 1033 of his glass plates which I have scanned and catalogued for the Museum. Some of the glass plates have a D-max of over 2.5 and a D-min of just a bit over the clear glass. They print beautifully with untoned Salt Prints. We have been able to acquire only a very few of his final contact prints. They seem to be Albumen which is really very much the same as Salt.

Will most certainly also try to final Selenium tone the prints... cross toning I can only hope for.

After testing Salt with Rodinal Processing will post results... guessing a month from now.

29-Apr-2016, 05:39
I had wanted to do so earlier, but I did some testing this morning with the concept of salt prints developed in rodinal. In fact, I used parodinal, which I also use to develop x-ray film.

Some observations:
* I started with coating the paper I always use for alt process printing with 2% NaCl, drying with a hairdryer, then coating the same amount of 10% AgNO3 on top, with about 1 drop of 40% citric acid added per 10-20 drops of AgNO3. Exposed for about 2 minutes at a few inches from my face tanner through a contrasty x-ray negative. This is roughly 25% of the exposure a regular salt print requires in my setup. Developed in a solution of one teaspoon (about 2ml) of parodinal in 200ml water. Print came out more or less pitch black all over the image area and solarized upon drying.
* I then tried coating and exposing in the same way, but rinsing the print to remove unexposed silver chloride before developing it in the parodinal. This resulted in a greenish-brown print, quite dense overall but not by far as dense as the previous attempts, with virtually no detail or contrast.
* I then tried for a drastic decrease in exposure with the same emulsion: 30 seconds at about 15 inches, or a small fraction (let's say about 5% to 10%) of the exposure a salt print normally takes. Development in a slightly more dilute parodinal (about 1 ml to 200ml water) for 1 minute gave a rather murky, greyish-brown print, with grey highlights (actually about halfway in density between clear paper and the limited dmax) and brownish shadows with a golden hue.
* I tried eliminating the citric acid from the emulsion, and got a print that showed virtually no contrast and basically was at dmax all over the coated area. So I went into the other direction and made an emulsion of 10 drops of 2% NaCl (coated and dried on A5 or roughly 5.5x7.5"), followed by 10 drops of 10% AgNO3 with 4 drops of 40% citric acid added, so four times as acidic as my initial attempts. This resulted in a slightly paler print than before, that also was more brown (a bit like Van Dyke), with poor dmax and still grey, bland highlights. As I watched the print develop, I noticed that the development began promising, with clear highlights, but the highlights quickly became darker. I hypothesized that the developer needs to be restrained in some way in order to prevent the highlights from fogging.
* Final try was the same emulsion as above with 4 drops of 40% citric acid added to the AgNO3. Exposure shorterened to 15 seconds at 15 inches. I modified the developer, still about 1 ml of parodinal to 200ml of water, and added 24 drops of 40% citric acid to it in order to tame the developer. About 1.5 minutes of development gave a very grainy, but contrasty print with reasonable dmax, grey midtones and grey-brown shadows. Tonality however is very poor, with coarse gradations and the texture of the paper is much more visible than in other prints. The result looks a bit like my poor tries at brush-developed gum printing. The fogging in the highlights was virtually gone though.

I may give it a few more tries to see if I can work something out that gives decent contrast, smoother tones and no fogging. I can see a potential advantage in this approach, as it seems to be capable of yielding more contrasty prints than normal salt prints. The gigantic increase in printing speed somewhat surprised me at first, but from a chemical viewpoint, it seems to make sense. The process is essentially made from a print-out-process (regular salt) to more of a develop-out-process (parodinal developed variant). I can imagine that some contrast control can also be fashioned by varying the exposure and development times, just like with regular film and prints.

Edit: some scans of the prints discussed above.
#1: first quasi-successful attempt. 10 drops 2% NaCl, dried, 10 drops 10% AgNO3 + 1 drop 40% citric acid, exposed 30 sec @ 15", developer ca. 1ml parodinal in 500ml water for 1 minute, brief rinse, fix in 5% thio for about 1 minute, brief wash.

#2: increased citric acid in sensitizer. 10 drops 2% NaCl, dried, 10 drops 10% AgNO3 + 4 drops 40% citric acid, exposed 15 sec @ 15", developer ca. 1ml parodinal in 200ml water for 1 minute, brief rinse, fix in 5% thio for about 1 minute, brief wash.

#3: acidified developer. 10 drops 2% NaCl, dried, 10 drops 10% AgNO3 + 5 drops 40% citric acid, exposed 15 sec @ 15", developer ca. 1 ml parodinal + 24 drops (ca. 1 ml) of 40% citric acid in 200ml water, developed about 3 minutes (until shadows looked about right), brief rinse, fixin 5% thio for about 1 minute, brief wash.

Ignore the greenish tinge in the highlights. My scans from prints are always horrible in terms of color accuracy; I tried to match them as well as I could by eye on my laptop monitor with the prints held in overcast daylight.

Coating is horrible as you can see, which is mostly due to my technique, but this process also seems to emphasize any imperfections in the coating and print surface.

Tin Can
29-Apr-2016, 11:29
Great info and documentation. I'm sure it helps to have an interesting subject on the test negative. :)

I am only researching Salt Printing now, but have necessary components gathered. I also follow/lurk a certain newsgroup.

I need to locate my 4x5 printing frame, it's here somewhere...

Little by little as my friends say.

Thanks for a great post!

29-Apr-2016, 13:11
Thanks, and it's great to hear you found my post worthwhile!

To be honest, I have only managed to get a decent salt print once or twice. On unsized paper, I've always found the results unimpressive. On gelatin-sized paper, the prints are much more brilliant, but the problems with coating irregularities only get worse...

On the subject of getting an even coating, I've tried several approaches. Hair brush (good quality synthetic), foam brush, a PVC puddle pusher...only the hair brush produces good results with sensitizers that are actually solutions and none of my approaches has worked so far for emulsions that are actually suspensions (e.g. silver chloride or silver oxalate). I feel that if I somehow manage to find a solution for this (long shot...), the (pa)rodinal developed salt prints (let's call them 'saltinal' prints) should be feasible.

I've experimented a little more today, with 'saltinal', Van Dyke Brown and also kallitypes made with ferric ammonium oxalate (FAO). The sensitizer for both the salt prints and the FAO-kallitypes suffer from the same fundamental issue: the light-sensitive silver compound (silver chloride and silver oxalate respectively) are virtually insoluable and therefore form a milky suspension upon mixing. With classic salt prints, this is 'solved' (or rather, worked around) by coating the two parts of the sensitizer separately. However, I virtually never manage to get an even coating, even with classic salt prints. With FAO-kallitypes, I have exactly the same problem. Coating the FAO first, drying the paper and then coating the silver nitrate does help a bit, but I've never gotten a perfectly even print.

Nevertheless, I tried the other route with both salt and FAO-kallitypes today: mix the sensitizer and allow the silver compound to drop out of solution, and apply the sensitizer suspension in one go. Depending on my luck, that either produces the same coating uneveness as when I apply both solutions separately, or the result is a bit better. But something else happens as well: both the FAO-kallitypes and the 'saltinal' prints I made by applying the suspension sensitizer come out in a very neutral tone - albeit with very limited dmax. Both processes produce quite pronounced, colorful hues when the sensitizer is applied separately (and much better dmax, especially the FAO-kallitypes). I think the explanation could be that when mixing the sensitizer before coating it, the silver particles that are formed are much larger than when they are formed on the paper by applying the solutions separately. My understanding is that fine silver particles will produce a wide range of colors, depending on their exact size and shape, while larger particles will produce neutral grey/black tones. But since the particles are in suspension if the sensitizer is mixed before coating, they won't sink into the paper fibers well and wash off during processing, causing the low dmax. I've tried adding a surfactant to the mixed sensitizer in the hope that it would sink into the paper better this way, but it seems to make little difference.

Long story short: it seems to me that coating is the crucial step in getting the 'saltinal' prints to work. And as it happens, I'm pretty horrible at coating (although I have less problems with cyanotypes and Van Dyke Browns)...