Latent Image MASK
An element consisting of two images made by different printing methods with the same colour. The first (bottom) image is printed by offset, the second image is printed by intaglio over the first one. The top image can be observed under reflected light, the lower image becomes visible in transmitted light (fig. 1).
a
b
Fig. 1. Latent image MASK. 20 Gibraltar Pounds (2011):
a – view under reflected light; b – view in transmitted light