KB73959693: Color Engine Pilot - Recommended aperture for spectrophotometers in relation to the ruling of a printed sample

Context

This article describes the recommended aperture sizes for color measurements of screened samples.

Procedure

There is a correlation between the lineature of printed samples and the aperture of a spectrophotometer that will give you error-free measuring. The following aperture sizes are recommended:

• 1.5 mm instrument, for 2mm patches, for screening of 175 l/inch, 69 l/cm or above
• 2 mm instrument, for 3 to 5 mm patches, for screening of 133 l/inch, 52 l/cm or above
• 4 mm instrument. for 5 to 6 mm patches, for screening of 65l/inch, 26 l/cm or above
• 6 mm instrument for large patches (e.g. in packaging)

You notice that it is not recommended to measure samples with a ruling less than 65 LPI with spectrophotometers like a X-Rite i1 which has a 4.5mm aperture.