1973: punched cards
The difference with the previous painting by hand is not in the algorithm, which is the same as before, but in the realization.

The cards have been used in two ways:
- as a support for the work,
- as a mask for a given color to be spread on the support

The IBM 1130 has a puncher of cards in output, we have to adapt the program in order to decide the positions occupied by one basic color on the card, and program (necessarily in fortran) the corresponding punch..

The support was constitued by two cards completly perforated, surimposed so that there are no holes, producing an effect of matter.
For the painting: we used a roller to spread the color through the cards-mask over the background , what was much faster than to paint every point by the hand, even if we had to wait for drying between the differents basic colors.
The resulting painted cards were sticken on wood.
The card becomes a stencil for the color.
Practically we had to be very patient again, because the result was composed of many cards, and we had to take care of their spatial disposition. detail of the method: examples of "stencils" and programs
exposition à l'Espace Cardin 1973