Acid-free

Also known as heliogravure, photogravure is arguably the finest photomechanical means of reproducing a photograph in large editions. Copper plates are acid-etched directly from an original silver print; the etched areas then hold differing amounts of ink in order to correspond to the tones of the original print. If prints remain untrimmed, the impression of…

Dye, unlike pigment, dissolves completely in solution (pigment-based inks leave tiny particles floating in the solution). This means that dye-based inks are entirely absorbed into the paper that they are printed on – the image is in fact a highly controlled stain. The resulting images can thus appear very slick and even, with a vast…

CMYK is an industry standard abbreviation for cyan, magenta, yellow and black. These are the colours used in standard four-colour printing (as in inkjet and Iris printers).

Digital colour coupler Colour coupler prints, or chromogene prints, are very similar to standard C-type prints, but the silver salts ‘couple’ with coloured dyes, rather than being replaced by them. The end result is very similar to standard C-type prints. Colour coupler prints have the benefit of using the same extremely light-sensitive silver salts as…

Toning, or toned black and white: toning images allows an artist/printer to alter the colours of a photographic print (by replacing the silver in the silver salts with another metal). Toning can be used as an aesthetic decision by the artist, or it can also be used to improve the archival properties of a print….

A particular type of reversal (R-type) colour paper and printing process which gives strong colours (often with striking reds) and creates a long-lasting print. Printing in this way from a positive image results in exactly the same colour saturation as the original, and greater contrast.