To avoid spreading trays all over my darkroom, I recommend carrying out all processing in just one tray, with a good water rinse between steps.
Prepare the sensitizer by mixing equal parts of Solution A (10% silver nitrate) and Solution B (20% ferric oxalate). About 2ml of combined solution is adequate for an 8X10 print, or the equivalent.
3) Dry the Sensitized Paper
Contrast can be controlled by the addition to the developer of a few ml of a 5% potassium dichromate solution. The practical limit ranges from as little as 1 ml per liter of developer up to about 16 ml per liter. This allows the use of negatives from a DR as low as about 1.2 to a maximum of about 2.2. If too much dichromate is added, printing times will increase considerably and the image will take on a granular look.
The developer can be reused, but should be replenished. I recommend replenishment at the rate of about 200 ml of developer per every 500 square inches of print surface developed. To replenish, decant the developer from the top of the bottle and discard the solution on the bottom: if the developer is not replenished, the accumulation of ferrous iron will make it increasingly difficult to clear the print during processing. This will not only result in an unpleasant stain in the masked areas of the print, but may also decrease permanence, because the stain consists in large part of residual ferrous iron.
After development in sodium citrate, the print will have a rather unpleasant brown color, but do not despair. Subsequent processing will change final image color quite dramatically.
5) First Rinse
After development, rinse the print for 1-2 minutes in running water. It is very important that this first rinse be done in water that is either neutral or slightly acidic. If the first rinse is alkaline, ferrous hydroxide compounds may be formed in the paper, making complete clearing difficult or impossible.
Clear the print until there is absolutely no stain left in the sensitized but unexposed areas of the print. The time for the paper to completely clear will vary with different papers, and sometimes even with the same paper manufactured at different times. However, if the paper takes more than about four minutes to clear, I would consider it unsuitable for kallitype and look for a better one. Renew citric acid bath frequently, as this chemical is very inexpensive and proper clearing is absolutely vital to print stability. The image will lighten considerably during clearing, but don't worry because all the lost density will return during toning and fixing.
7) Second Rinse
After clearing, rinse the print for 30-60 seconds in running water.
Tone for the time necessary, which can vary from 5-20 minutes depending on the strength and amount of toner. With most toners, toning begins first in the highlights, proceeds to the midtones, and ends with the shadows. The print is fully toned when the shadows have taken on the color that is characteristic of the toning metal. With the toner used full strength, the print should be fully toned in about six to eight minutes.
9) Third Rinse
After toning, rinse the print in running water for 60 seconds.
Fix for four minutes. For maximum archival quality, use two separate fixing baths and fix for two minutes in each, with a 30-second rinse in running water between. The second bath should always be fresh fixer.
11) Fourth Rinse
After fixing, rinse in running water for one minute.
12) Hypo Clear
After the fourth rinse, place the print in a 1% solution of sodium sulfite for two minutes. Or Kodak Hypo-Clear can be used.
13. Final rinse
Rinse the print in running water for 20-30 minutes. If you omit the hypo clear bath, final wash time should be an hour.
Hang the print to dry, or place on a drying rack.
Refinements to the Process
As you begin to work with kallitype you will learn that there are literally dozens and dozens of variations of the process
, ranging from developer formulations capable of rendering a wide range of colors and tone, to sensitizer additives
which can alter color and tonal range. For the most part, I would recommend sticking with the sodium citrate
developer until you become very familiar with the process. In fact, there is really no reason to use any other developer
unless you want an unusual color that cannot be rendered through toning with gold, platinum or palladium. However, as
noted earlier, the permanence of kallitype prints in which silver has not been replaced by toning with one of the more noble metals is highly suspect and I recommend that for maximum permanence you always tone.
The addition of small amounts of certain metallic salts to the working sensitizer can modify the color and tonal range of the final image and also, in combination with double toning, produce interesting split tones in the image. The metals most commonly used are gold, platinum, palladium, and mercury. The effects obtained by adding the metallic salt directly to the sensitizer are different from toning.
Gold Additive — Prepare a gold chloride working solution by mixing 5ml of a 1% gold chloride solution with 20ml distilled water. Add the working solution to the sensitizer at about 1 part gold working solution to 9 parts sensitizer. The addition of gold will give a warm brown-olive tone to the final print.
Platinum or Palladium Additive — Prepare a platinum or palladium working solution by mixing 5ml of potassium chloroplatinite 20% solution or sodium chloropalladite 20% solution with 20ml of distilled water. Add the working solution at the same ratio as gold, one part working palladium or platinum solution to 9 parts sensitizer. The addition of platinum or palladium will give a neutral black or a warm black, depending on which metal is used.
Mercury Additive- — Prepare a concentrated mercury solution by mixing 1g of mercuric chloride with 30ml distilled water. Add the working solution to the sensitizer at the ratio of about 1 part working solution to 20 parts sensitizer. Expect a warm olive tone, but results can be somewhat unpredictable. Handle this solution with maximum care because mercuric chloride is a hazardous substance.
Unfortunately the employment of metal has one important negative effect. The image is more likely to stain and the print will be much more difficult to clear. Stevens suggests that use of nitrates of gold, palladium and platinum instead of the chlorides will eliminate staining, but those compounds are not readily available.
Should you become seriously interested in the use of metal additives, I would recommend further reading in Dick Steven's book, Making Kallitypes: A Definitive Guide, pp. 92-95 .
Many people like the native color of kallitype prints and do not tone them. In my opinion, this is a mistake, because toning provides much greater image permanence. In fact, I am convinced that all untoned kallitype images will eventually fade, as it is impossible to remove all residual ferrous iron from the paper, and if any at all remains it will eventually cause the silver to oxidize, ultimately leading to fading. This may take several decades but is, I believe, almost certain to happen.
Although the major reason we tone kallitypes is for permanence, toning has other benefits. One of the primary benefits is that images toned before fixing with gold, platinum or palladium will not fade in the fixing bath. The major reason for fading, or image recession during fixing, is bleaching of the silver. An image toned with one of the more noble metals will not fade or recede in fixing because the silver has been replaced with metals that do not bleach.
Still another reason to tone is that it eliminates the effects of solarization. In heavily exposed areas we frequently see tone reversal in untoned kallitypes, that is, with increasing exposure the shadow areas actually get lighter. This look can be very unpleasant. Toning with gold, platinum or palladium counteracts tone reversal and restores normal tonal values to the heavily exposed shadow areas.
Finally, through double toning, in which more than one metal is used to tone the print, it is possible to produce a variety of tones and colors in the Print, an effect which can be both intriguing and aesthetically pleasing.
Note that the toning formula in this article are based on mixing 1-liter amounts. However, for maximum consistency I suggest that you tone as a one-shot solution, using the minimum amount of fresh solution possible, and then discard after use. You will need approximately 20ml of solution to fully tone a 5X7” image, or the equivalent for larger images. However, using such small quantities of toning solution requires a flat tray with no ribs or grooves.
Gold Toner #1
This toner does not keep particularly well so it is best to mix it in small quantities just before it is needed, and of course discard after use.
Gold Toner #2
This toner keeps well and retains its working characteristics even after moderate use. However, I strongly recommend that you use as little solution as possible to tone and then store the used solution in a separate bottle so that the fresh solution does not become contaminated.
One of the interesting qualities of Gold Toner #2 is that it works on all areas of the print — shadows, midtones and highlights — at about the same time, unlike Gold Toner #1, which works first on the highlights, then progressively on the midtones and shadows.
Platinum and Palladium Toner
In selenium toning, metallic silver is converted to a silver selenide, which is highly resistant to the effects of oxidizing agents. In practice it is extremely difficult to get satisfactory results with selenium when toning is done before fixing, because it reacts with residual silver nitrate in the paper and causes staining. For this reason, I recommend that toning with selenium be done after fixing. This will require an adjustment in exposure time because there is more recession, or bleaching, during fixing of an untoned image.
Selenium Toner #1
To prepare a stock solution,
A working toner is mixed by adding 100ml stock solution to water to make a total of 1000ml, or the equivalent. Stronger solutions give browner prints, weaker solutions, cooler tones.
Selenium Toner #2
Kodak Rapid-Selenium 10ml
Double toning is used to produce what is known as split toning, i.e. parts of the image are toned with one metal, with
its characteristic color, and other parts are toned with another metal. This kind of toning must begin with the most
noble metal, either platinum or palladium, and be completed with the least noble, gold. This is because the most noble
metal will always replace the least noble and if toning is done first with gold, and followed to completion with platinum or palladium, the image will look as if it has been toned in just platinum or palladium..