Antique Prints Faults and the Corrections Applied

ORIGINAL IMAGE	FAULT	CAUSE	CORRECTED IMAGE
	Discoloured or beige/brown toned paper	Long term exposure to atmospheric pollution especially from coal and tobacco smoke. Failure of bleaching agents over time.
	Altered tones and colours	As above plus medium to long term exposure to ultra-violet light (sunlight). Early coloured inks generally take on a blue or green cast with partial or major loss of reds. Some metal based pigments become seriously over saturated
	Spotting	Decomposed organic material, usually skin flakes, louse and mite faeces or their crushed whole bodies or body parts. Ink and paint splashes.	Corrects to clean blank paper
	Foxing	Fungal and microbial staining usually associated with degradation of organic detritus either in the body of the paper itself or as a follow-on effect from spotting. Greatly accelerated in a damp environment.	Corrects to clean blank paper
	Engraving Errors	Mistakes made but left uncorrected as the only alternative was to scrap the plate and start again.
	Blurred Outlines	Migration of wet ink along paper fibres, rough paper surface or movement of plate relative to the paper during the impression process.
	Discoloured outlines with stained margins.	Decomposition and oxidation of organic ink binders, particularly guar gum and linseed oil..
	Colour overruns	Hand coloured prints Careless original colouring. Other prints Low quality printing resulting in poor registration of colour plates - rushed work.
	Colour Bleeding, one of the most common faults.	Careless original water-colour work usually the result of an overloaded brush or colouring an adjacent area before the first one has dried properly..
	Dark Patches and Stains .	Unprotected or damp storage. Handling with greasy or dirty fingers Poor quality control in the paper making process.	Corrects to clean blank paper
Mechanical damage	Rubbing and Scratches. Tears and Creases. Tunnels and holes.	Ill considered attempts at cleaning. Rough handling. Poor storage. Insect attack.	Invisibly repaired.
	Poor Definition	Low quality, mass produced prints. Typical of most lithographic, and almost all 20^th Century commercially produced prints and publications.	Cannot be corrected.