A Practical Approach to N-Value

The variation of the Yule-Nielsen n-value is investigated by analyzing different inks printed on the same type of stock at a constant screen ruling. Sheets were collected at random from actual production press runs and dot area was calculated by measuring diameter with a highly accurate optical gauge. Densities of the tint screen and the accompanying solid patches were measured with a Status T densitometer through all four filters. The value of n was then derived through an iterative process. N is shown to vary substantially given these conditions.