View Full Version : Initial Salt Print Test

04-07-2006, 12:23 PM
As usual, I have tried to include too many variables at one time in my testing. However, I think that there is some valuable information that I can pass on to anyone wanting to try salted paper. The attached image is a composite of four salted paper prints using a standard 4X5 Stouffer 21 step test negative.

The paper is 140 lb Lanaquarelle HP, which is a pretty absorbent paper. I used two different methods for salting the paper: two of the sheets were soaked in 2% sodium chloride solution for 2 minutes and then allowed to dry. The other two sheets were soaked in solution of 2% ammonium chloride and 2.8% (by weight) gelatin. I used regular Knox gelatin from the grocery store. I soaked the sheets in the gelatin/salt solution, then pulled them between the edge of the tray and a glass coating rod to squeegee as much excess gelatin off the surface as possible. As you can see from the mottled appearance, I did not remove nearly enough of the excess, and the silver nitrate solution did not adhere uniformly.

The silver nitrate is 12% by weight (12 g silver nitrate in 100 cc distilled water). It was applied with a 1.5 inch wide hake brush - which can be purchased with no metal - the bristles are held to the handle with thread. One sheet of each salting method was coated once, the other coated twice (the first coat was allowed to dry before applying the second).

The exposure used my homemade split back contact frame and my 13 w spiral BLB fluorescent black light. The exposure times were 20, 40, 80, and 160 minutes.

Here is a summary for each image:
1. NaCL, no sizing, two coats Silver Nitrate, 20 minutes.
2. NaCL, no sizing, one coat Siver Nitrate, 40 minutes.
3. NH4CL + gelatin, one coat Silver Nitrate, 80 minutes - the gelatin stained in the wash on this sheet because I let the wash water get too warm.
4. NH4CL + gelatin, two coats Silver Nitrate, 160 minutes

The processing steps were as follows:
1. 4 minutes distilled water
2. 4 minutes fix #1 - plain hypo fixer, mixed 150 g sodium thiosulfate + 2 g sodium carbonate per liter. I used 500 ml for each fix bath.
3. 4 minutes fix #2.
4. 4 minutes distilled water.
5. 4 minutes Kodak hypo clearing agent, working strength.
6. 30 minutes running water wash. Attached files http://f295.f295.org/uploads/salttestsmall_7488.jpg (http://f295.f295.org/uploads/salttestsmall_7488.jpg)

04-07-2006, 12:32 PM
Observations and conclusions:

1. The paper that I used is pretty absorbent. I think that this process wants a pretty hard and smooth finish if it is to be used without gelatin or starch sizing.
2. I would like to perfect the gelatin sizing, as the image is much richer and darker if the sensitizer is not allowed to soak in to the fibers of the paper.
3. I see no difference between Ammonium chloride and sodium chloride. I used some pickling salt that I had left over from last summer's dill pickles - pure NaCl.
4. It looks like this process (with this lamp) will print 14 or 15 distinguishable steps on the Stouffer scale. This translates to 7 zone system zones. I think that salt prints want a very long contrast scale. I suspect that a print made in the sun might show an even longer scale.
5. I did not try toning the prints yet. After I get the paper, salting, coating, and exposing down to where I can get the same thing twice in a row, then I will try toning with selenium. I am hoping that the deeper black will make the print look snappier. The unsized paper prints look pretty flat. If I can get everything to where I have confidence in the whole process, then I might spring for the chemicals to do gold or pt/pd toning.
6. One coat of sensitizer will do the trick.

All in all, this is really fun. It is easy to do, but hard to master. I hope to make some images in the next couple of days. Stay tuned.

04-07-2006, 02:48 PM
how many lamps were you exposing with?

04-07-2006, 03:30 PM
how many lamps were you exposing with?

Just one bulb, in a cheap desk lamp, about 3 inches above the glass.

04-07-2006, 06:56 PM

04-07-2006, 11:32 PM

The exposure used my homemade split back contact frame and my 13 w spiral BLB fluorescent black light.

Black-light flourescent that screws into an incandescent type socket.

04-08-2006, 08:12 PM
I posted a real-life image in the alt process section over on the pinhole side.