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The intersection of grey dotted lines marks our target of 40 mg and an edge step of 1.0 absorption units. Each of the dots on the coloured lines represents a different diltution (you can inspect the values for mass and edge step in the table to locate each dilution on the plot). The results suggest that a total absorption of a little less than 2.0, i.e. ~1.85 and a dilution with cellulose to between 10 and 20 wt. % will give the optimum result.