Photographic Definitions: The Southampton International Exhibition uses the following definitions:
PSA Monochrome Definition
An image is considered to be Monochrome only if it gives the impression of having no colour (i.e. contains only shades of grey which can include pure black and pure white) OR it gives the impression of being a greyscale image that has been toned in one colour across the entire image (for example by sepia, red, gold, etc). A greyscale or multi-coloured image modified or giving the impression of having been modified by partial toning, multi-toning or by the inclusion of spot colouring does not meet the definition of monochrome and shall be classified as a Colour Work.