in most of the trials , results of both methods are similar in efficiency and generally consist of an increase of L*values.It is important to remark that trials with no presence of visible residues on the surface and/or ink loss reveal that increase in lightness is due to removal of greyish dirt. As usual ,cleaning might be clearly noticeable to the naked eye depending on the degree of dirt . In some cases these differences are not perceptible a visa
It is important to remark that colour results do not seem significanly influenced by residues remaining on the surface of some treated documents ,which tend to be similar when treated with erasers or microblasting . colour measurements conducted after one year of storage showed no significant changes in any of the treated prints.