April 05
Prof. Ismael H. F. Santos -  ismael@tecgraf.puc-rio.br                                                          2
C + M + Y = K  (black)
 100
50
70
=
 50
0
20
50
+
C
M
Y
C
M
Y
K
CMY + Black
nUsing three inks for black is expensive
nC+M+Y = dark brown not black
nBlack instead of C+M+Y is crisper with more contrast