When measuring color...
What is the correct M factor setting for my spectrophotometer?
What does M Factor mean?
Is the M Factor important?
All great questions and common questions. It actually is an important specification to understand when setting up your spectrophotometer and measuring to various color standards. It is also important to divulge the M Factor setting when sharing your color measurement data with other parties (brand manager, prepress, ink room, and press room). CXF data captures this as part of the color exchange information.
Just as it is important to select the appropriate status response used for density measurements and the illuminate, observing angle, and DE tolerancing formula for color measurement, we must decide on an appropriate setting for the M Factor setting.
So how do I know which M Factor I should be using?
How to decide which M Factor setting to use is dependent on the standards to which you are measuring and how those values were established. Older standards are based on M0, but newer standards, such as ISO 15339 (includes CRPC 1-7 and GRACoL 2013), were based on M1. Below is a general breakdown for M0, M1, M2, and M3. You may also reference this link for a more detailed Xrite white paper explaining M Factor.
