Instrument Apertures & Accurate Dot Measurement
How to decide which aperture size is appropriate for your workflow when reading color bars or taking density measurements?The green section of the following table was extracted from ANSI CGATS.4-1993 Appendix C. It in turn refers to ANSI/ISO 5/4:1983. The last three columns illustrate compatibility with X-Rite's new instrumentation.
| Nominal Screening Frequency | Sampling Aperture | X-Rite Instrument | ||
| lines/inch | lines/cm | minimum size (mm) | 5xx Microspot | ATS Pub |
| 65 | 26 | 3.5 |
NO NO NO | |
| 85 | 33 | 3.0 | ||
| 100 | 39 | 3.0 | ||
| 120 | 47 | 2.0 | YES | YES |
| 133 | 52 | 2.0 | YES | YES |
| 150 | 59 | 2.0 | YES | YES |
| 200 | 79 | 1.5 | YES | YES |
| 300 | 118 | 1.0 | YES | YES |
