Gold toners

HCA should be used after selenium toning and before washing. HCA is unnecessary after other toners unless re-fixing is indicated (for example, Nelson Gold Toner partial redevelopment/ toning, etc.). 

Those which bond an inorganic compound directly to the silver in the image, in effect coating it (Formulas Toners Kodak GP-1 and GP-2 Gold Protective Solution and Nelson Gold Toner). 

Red tones can be achieved through the use of a direct toner, such as GT-15, or by combining toners. Try a combination of Ansco 221 Sepia Toner and Blue Gold Toner. Follow the directions published with Ansco 251 Green Toner for washing between processes. 

Secondly, with one main exception, the silver that has been toned by one of these archival toners is stable and is left unaffected by almost any chemical used subsequently. The one main exception is that when immersed in gold toner, sepia-toned silver does change color towards salmon/orange/red, depending on the paper emulsion and the way the sepia toner is made up. 

NOTE Prints should be well washed between toning baths and in particular acidic prints (for example, from direct gold toner, acid stop baths, etc.) can stain if transferred straight to selenium without being well washed, or put through alkaline hypo-clearing agent. 

Like all gold toners, the action is more effective if performed slowly. Adjust the gold or water content to require between 5 to 10 minutes at room temperature for complete toning. 

Using Nelson Gold Toner, three-dimensional brown tones can be obtained that vary from a hint of warmth to rich brown sepia browns. The depth of tone depends upon the duration of time the print remains in the toning bath, from 5 to 20 minutes. 

Because gold and silver salt toners are very expensive, selenium toners in diluted, commercially prepared form are presently used. If the toner is heated, poisonous hydrogen sulfide gas can be released. 

If you intend to gold-tone a print for blue tones, do not add too much carbonate solution as it will make it difficult to secure a brilliant blue with gold chloride toner. 

There are three ways to achieve cold tones. The first is through direct development of bromide paper. The second is through the gold-toning of a warm-tone chlorobromide paper. The third method is immersion in a blue-toning bath (Formulas Toners, Ansco 241 Iron Blue Toner). 

The classic formula for gold protective toning is Kodak GP-1 Gold Protective Solution. Like selenium toner, GP-1 not only protects the print but causes a minimum color shift. What shift there may be is toward a slight blue-black that some photographers find pleasing. With some papers, GP-1 will also improve separation in the highlights. 

The 6-T system consists of three separate bleaches, three separate toners, a sodium chloride solution, plus a gold-tone modifier. By mixing and matching the various bleaches and toners, and throwing in the chloride bath and/or the modifier, a large variety of tones can be achieved from purplish-brown to a bright sunlit sepia. This system works best with old-style soft emulsion papers. (Formulas Toners DuPont 6-TToning System)... 

When using archival toners, I most commonly use sequential combination toning rather than a single toner, especially selenium + gold, selenium + sepia,... 

As a rule, acid toners, such as PO P. Borax Toning Bath, act slowly and tend to be warm alkaline toners, such as P.O.P. Thiocyanate Toning Bath, act more quickly and tend to be cool, or blue. If gold toning is intended, trim the darkened edges from around the print so that you don t waste gold solution. 

The following table indicates the effect obtained by gold modification after toning in the various bleach-toner combinations. 

When modified, the 6T-3 toners produce less purple colors than the 6T-1 toners. All gold tone modified prints change color somewhat on drying and this cannot be avoided. The color descriptions given above apply to the dried prints. 

To facilitate the measurement of the bulk conductivity, the toner powders were compressed into thin cylindrical disks under a hydrostatic pressure of 100,000 psi. Under these pressures the toner flowed readily and formed a uniform pellet in which the toner particle surfaces were in more intimate contact than in a loose powder. Gold electrodes were evaporated onto the flat faces and the current as a function of the applied electric field measured. This measurement method of the conductivity has certain inherent disadvantages, however, this measurement was intended to be used simply to contrast the kinetic conductivity values reported in Section IV, not to extract absolute values of the material parameters. Nonetheless, several samples of various thicknesses were prepared and measured for each type of toner and the results were found to be quite reproducible. 

Figure 11. Equivalent circuit of the toner-developer-gold plate shown in Fig. 10. Key VA, applied voltage CT, developer-gold plate capacitance Rt., effective resistance represented by the current-voltage pre-amp and V output signal.

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