The following table was extracted from ANSI CGATS.4-1993 Appendix C. It in turn refers to ANSI/ISO 5/4:1983.
Nominal Screening Frequency | Sampling Aperture | |
lines/inch | lines/cm | minimum size (mm) |
65 | 26 | 3.5 |
85 | 33 | 3.0 |
100 | 39 | 3.0 |
120 | 47 | 2.0 |
133 | 52 | 2.0 |
150 | 59 | 2.0 |
200 | 79 | 1.5 |
300 | 118 | 1.0 |