A first pattern and the second pattern in an original include relatively lighter markings within a relatively darker background. The first pattern differs from the second pattern by including non-printing patches between the relatively lighter markings. When the original is exposed to ultraviolet light, the underlying print media fluoresces in response to the ultraviolet light at the non-printing patches, revealing hidden security printing features. When a scanned image is printed on a second sheet of print media to produce a copy of the original, the copy lacks distinct markings at locations where the relatively lighter markings and the non-printing patches appear in the original because the spacing interval of the relatively lighter markings and the non-printing patches is below the minimum resolution of the scanner. Thus, when the copy is exposed to ultraviolet light, the copy does not fluoresce the ultraviolet light where the non-printing patches appear in the original.