The Basel School of design offers a large range of publicly available courses on all kinds of creative fields. To advertise the courses of the 2014 fall and 2015 spring semesters the leadership of the Basel School of Design invited a group of students to create a poster concept. The posters would have to be printed with the school's plotter. To counteract the bad printing performance of the plotter with large, solid colour areas; I implemented an optical colour illusion using small dots in magenta and yellow to result in the salmon colour.