The MARTE viewer was manufactured in Spain in the
early 1960s. It is made from a hard, brittle plastic which is easily
cracked. That probably explains why these viewers are so rare today.
The viewer itself is large and feels quite
'chunky'. The picture cards it takes are large also, measuring 200mm x
100mm and containing just six stereo pairs, each picture being
20mmx20mm. The film used suffers from a common problem that of loosing
its colour pigment over time, eventually fading to a magenta monochrome
finish, but the detail in the pictures remains good.
Notice the lenses are riveted in place and the
main body is screwed together. Cards are manually advanced from the top
down with a spring engaging in a hole on the slide, to assist with
positioning. The view description is visible in a small windows between
and beneath the viewing lenses.