Palladiotype

In photography, palladiotype is a monochrome printing process, a rather obscure variant of the platinotype.

The process was in use after World War I, because the platinum used in the fairly popular platinotype quickly became too expensive for use in photography.Photographers tried to replace the platinum with the much cheaper palladium which gave similar effects. The cost of this metal, however, started to rise too and eventually, around 1930 the process was abandoned in favor of more economical processes.

Characteristics of a palladium print, compared to a platinum print:
*A warmer tone;
*Easier to solarize (see: Sabatier Effect);
*Large tonal range, up to D= 2.1, thus requiring a contrast-rich negative for printing;
*Deeper blacks, with a higher maximum density;
*A softer image, with delicate highlights.

References

* [http://www.alternativephotography.com/process_platino.html The Platinotype process]