Hypo-Alum Sepia Toner produces brown to reddish-brown tones on almost any print. The actual hue that you will obtain depends upon the toning time, upon the paper, and upon the speed of the paper. The use of silver nitrate and potassium iodide is optional, the silver nitrate can be used to decrease the ripening time and the potassium iodide gives a toning solution that yields warmer tones. There are a number of different formulations in the photographic literature that are called "Hypo-Alum Toners". All of these toners act by the deposition of silver sulfide on the print. They differ from one another principally in the amounts of the ingredients used in their preparation.
A split tone effect with deep blue shadows and brown highlights may be obtained by first toning in sulfur-based toner such as Hypo-Alum Sepia Toner, followed by an iron toner such as Blue Toner (GT-14), Iron Blue Toner, Iron Green/Blue Toner, or Ferricyanide-Iron Blue Toner (IT-6).
Unusual effects of mixed tones of blue-black shadows and soft reddish highlights can be produced by using prints which have been partially toned in a sulfide bath without initially bleaching the image. Hypo-Alum Print Toner may be used to carry out this type of sulfide toning. The well washed print is then toned in Gold Toner (GAF 231), Gold Toner (Ilford IT-4), or Gold Thiocarbamide Toner (Ilford IT-5) where the sepia tone will change to reddish brown and then to red.
Red tones may be obtained on prints that have been first toned in Hypo-Alum Sepia Toner, followed by Gold Toner (Ilford IT-4), where the sepia tone will change to reddish brown and then to red. Prints intended for this treatment should be dark and contrasty. Refixing is recommended.
CHEMICAL SAFETY
Silver nitrate is both an oxidizer (can supply oxygen to a fire) and a
caustic (can cause skin burns). Clean up any spilled solid silver nitrate with
water and dispose of any excess down the drain. Never dispose of solid silver
nitrate in a wastepaper basket. If solid silver nitrate comes into contact
with the skin, a chemical burn may result. Wash the area with cold water
followed by soap and water. Treat any wound in the same manner you would treat
a heat burn. When dilute solutions of silver nitrate are spilled on the skin a
brown to brown-black stain results. The color is due to silver metal bound to
the protein of the skin and cannot be washed off. While there are chemical
methods to remove these brown stains, the best procedure is to just let them
wear off.
MIXING THE TONER
You will need a 1 liter (or larger) mixing bowl and a 1 liter storage
container. The toning solution 15 mixed in four separate steps. The first and
second steps prepares the toner itself. The third and fourth steps are
optional and are explained below.
WORKING SOLUTION
Step 1
| Chemical | Amount | Units |
|---|---|---|
| Water (125°F/52°C) | 750 | ml |
| Sodium Thiosulfate (penta) | 300 | g |
| Water to make | 1000 | ml |
Place the not water in a mixing bowl and add the thiosulfate. Stir the solution until the solid goes into solution.
Step 2
| Chemical | Amount | Units |
|---|---|---|
| Solution from step 1 | 1000 | ml |
| Potassium Alum | 25 | g |
Add the alum to the solution obtained from Step 1 and stir the solution until the solid goes into solution. This solution can be used as such as a Hypo-Alum Toner. If you wish to do so, transfer the solution to the storage container. Skip to the instructions labeled "Final Dilution". If you choose this alternative, be sure to read the comments at the start of Step 3 and the section on "Ripening the Toner."
(Optional)
A solution containing only thiosulfate and alum will act as a reducer and
bleach a print by removal of the silver. When the silver concentration in the
bath is high enough, the solution will act as a toner. In order to convert a
fresh thiosulfate-alum solution to a toning bath, silver must be added. This
is carried out in two stages, silver nitrate is added to the bath and scrap
prints are toned in the bath until a satisfactory toning solution is obtained.
| Chemical | Amount | Units |
|---|---|---|
| Silver nitrate | 0.12 | g |
| Water to make | 1000 | ml |
Add the water to the vial containing the silver nitrate.
Add the silver nitrate solution to the solution obtained from Step 2. If a precipitate should form, ignore it. Stir the solution to ensure it is homogeneous.
Step 3 (optional)
The toning solution as described above tends to give cold tones. If you
wish to obtain warmer tones, then
potassium iodide must be added.
| Chemical | Amount | Units |
|---|---|---|
| Water (68°F/20°C) | 50 | ml |
| Potassium Iodide | 1 | ml |
Place the water in a clean mixing bowl (such as a water glass) and add the potassium iodide. Stir the solution to dissolve the solid. Pour the lodide solution into the bath obtained from Step 2 (or Step 3). A precipitate usually forms, especially if silver nitrate has been added to the bath. The precipitate is normal, therefore just ignore it.
FINAL DILUTION
Transfer the toning solution to its storage container and add sufficient
water to bring the final volume in the container up to 1000 ml. Cap and shake
the container to ensure it is homogeneous.
RIPENING THE TONING SOLUTION
Without sufficient silver in the toning bath, prints will be bleached rather
than toned. Some of the required silver can be added to the bath (Step 3) but
the final amount must be added by allowing the bath and the silver on a print
to attain an equilibrium. To obtain the proper silver concentration, "tone"
scrap prints. The first five or so of these prints will be ruined. (The
actual number ruined will depend upon print size, density, etc.). The tone of
the scrap prints will improve as the bath approaches the proper ratio of
ingredients.
CAPACITY OF THE TONING BATH
The ripened bath has a very high capacity and can be used for years. It is
reported to improve with use. Add a little water (or better, fresh unripened
toner solution) from time to time to maintain its volume.
USING THE TONER
The print to be toned should be developed more than usual to obtain the
best result. All types of papers can be used but the exact tone will depend
upon the paper used. RC papers will tend to gray from loss of their optical
brightener in this bath. The toning bath should be used undiluted and at
120°F/50°C to minimize the toning time. Place the toning solution in a
plastic tray. Try to avoid transferring any precipitate to the toning tray
however, if some should be transferred, don't worry about it. Float the
toning tray in a larger tray containing hot water. Add hot water to the
larger tray from time to time to maintain its temperature. Immerse a wet
well washed print in the hot toning solution. Rock the toning tray to wash
the print with fresh solution and to keep any precipitate off its surface.
Tone to the desired hue about 10 minutes will be required. After toning,
wash the print in running water for 10-20 minutes. Use a wet cotton swab
to clean any scum off the print's surface.
NOTES
Higher temperatures give colder tones. Warmer tones can be obtained by
adding 1 gram of potassium iodide to
each liter of toner. Toning may be speeded up by placing the prints in
a 10% sulfuric acid solution for
1 minute and then transferring directly to the toning bath.
REFERENCE
Hypo-Alum Sepia Toner, Kit No. 06-0100,
Photographers' Formulary (800-922-5255).
Photo-Lab-Index, Section 15, Supplement 172, p. 62, 63, 65
The Darkroom Cookbook, Stephen
G. Anchell, p.161.